Thumbwheel Switch
A7BS/A7BL
Wide Range of Locking-type
Models Available
■ Character height of 4.8 mm makes for easy-toview display.
■ Installation is easy with snap-in mounting.
■ The series includes a complete range of lockingtype models that prevent accidental operation.
Ordering Information
Switches (Single Switch Units)
Model
A7BS
Screw mounting (front mounting)
A7BS-20@-S
Snap-in (front mounting)
Classification
(See note 1.)
With external stoppers
Terminals
Color
Output code number
06 (binary coded decimal)
07 (binary coded decimal, with component
adding provision) *3
19 (decimal code, with component-adding provision)
54 (binary coded hexadecimal)
55 (binary coded hexadecimal, with
component-adding provision) *3
Model
A7BS-206 *2
Solder terminals *1
Black
Light gray
Model
A7BS-206-1 *2
A7BS-206-S
A7BS-206-S-1
A7BS-207 *2
A7BS-207-1 *2
A7BS-207-S
A7BS-207-S-1
A7BS-219
A7BS-254
A7BS-219-1
A7BS-254-1
-----
-----
A7BS-255
A7BS-255-1
---
---
Light gray
Black
A7BL
Snap-in (front mounting)
Classification
(See note 1.)
Locking type
Terminals
Color
Output code number
06 (binary coded decimal)
07 (binary coded decimal, with componentadding provision) *3
Solder terminals *1
Light gray
Black
Model
A7BL-206 *2
A7BL-206-1 *2
A7BL-207 *2
A7BL-207-1 *2
Note: 1. The classification diagrams show 4 Switch Units combined with End Caps to create 4-digit displays.
2. The model numbers given above are for Switch Units.
3. Models with +, - displays can also be produced. Add "-PM" (+/- alternating display) or "-MP" (-/+ alternating display) after the "206" or "207" in the model number
(e.g., A7BS-206-PM, A7BS-207-PM-1, or A7BS-206-MP). There is no "-MP" type available, however, for A7BS-20@-S models.
*1. For models with PCB terminals, add "-P2" to the model number (e.g., A7BS-207-P2-1).
*2. Models with internal stoppers are also available. Add "-S@@" after the "206" or "207" in the model number and specify the display range in the @@. For example,
to specify the range 0 to 6, add "-S06" to the model number (e.g., A7BS-206-S06-1).
*3. Models with diodes are available. Add "-D" to the model number (e.g., A7BS-207-D or A7BS-207-D-1).
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(c)Copyright OMRON Corporation 2007 All Rights Reserved.
1
A7BS/A7BL
Accessories (Order Separately)
Use accessories, such as End Caps, Spacers, and Connectors with the Switch Units.
End Caps, Spare Units, and Connectors
Accessory
Color
End Caps (1 pair)
Spacer
Solder terminals
Connectors
PCB terminals
Light gray
Black
A7B-M *
A7B-M-1 *
A7B-P@ (See note.)
A7B-P@-1 (See note.)
A7B-C
A7B-CP
Note: The @ in the Spacer model number stands for a letter in the range A to U. (Refer to the table in the following explanation about Spacers.)
* The minimum ordering unit is 10.
End Caps
Spacers
End Caps are used on the Switch Units at each end and allow all the
Switch Units to be securely mounted to a panel. They come in pairs,
one for the left and one for the right.
x Spacers are used for creating extra space or gaps between the
Switch Units and have the same dimensions as the Switch Units
themselves.
x There are also Spacers with engraved characters or symbols that
can be used for indicating units, such as time and length. (Refer to
the following table.) Consult your OMRON representative for
details.
Symbol
Stamp
Symbol
Stamp
A
No designation
H
cm
B
C
D
E
F
G
SEC
MIN
H
g
kg
mm
J
m
K
qC
L
PCS
Q
x 10 SEC
T
0
U
•
Specifications
Switching capacity (resistive load)
Continuous carry current
Contact resistance
Between non-connected
terminals
Insulation
resistance Between terminal and
non-current carrying part
Between non-connected
terminals
Dielectric
strength
Between terminal and
non-current carrying part
Vibration resistance
Shock resistance
Mechanical
Durability
Electrical
Ambient temperature
Ambient humidity
Max. operating force
5 to 28 VDC or 50 VAC
1 mA to 0.1 A
1 A max.
300 m: max.
10 M: min. (at 500 VDC)
1,000 M: min. (at 500 VDC)
600 VAC, 50/60 Hz for 1 min
1,000 VAC, 50/60 Hz for 1 min
10 to 55 Hz, 1.5-mm double amplitude
490 m/s2 min.
100,000 operations min.
50,000 operations min.
Operating: -10qC to 65qC (with no icing)
Storage: -20qC to 80qC
Operating: 45% to 85%
5.39 N max.
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2
A7BS/A7BL
Dimensions
(Unit: mm)
Switches
A7BS-2@@(-1)
Solder Terminals
5.5
A
8±0.1
24
16
(Unit: mm)
*
24.5
2.8
Number of
Switches
(n)
20.6 22
2.6
Solder terminal
Panel thickness: 1 to 3
* If the output code is 06 or 54, the dimension is 32.5;
if the output code is 07 or 55, the dimension is 43.5.
3.8
Panel Cutout
22.4+00.4
3
0.8
6.9
B
C+0.3
0
P=8±0.2
Thumbwheel Switches with External Stoppers:
A7BS-20@-S(-1)
x Use A7BS-S Stopper Pins to make dial display restrictions for these Switches.
x Insert the Stopper Pins in the positions required to give the desired display range. For
example, for a display range of 0 to 5, insert a Stopper Pin at position 1 (see following
diagram) to stop the display from going above 5 when the (+) button is pressed, and insert
a Stopper Pin at position 2 to stop the display from going below 0 when the (-) button is
pressed.
Refer to page 7 for details.
5.5
2.8
32.5
24.5
9
22 20.6
9
1
7
2
6
16
4
16
24
32
40
48
56
64
72
80
88
14
22
30
38
46
54
62
70
78
86
14.4
22.4
30.4
38.4
46.8
54.8
62.8
70.8
78.8
86.8
Note: 1. The dimensions above include both End
Caps, and will increase 8 mm for each
Spacer inserted.
2. Unless otherwise specified, a tolerance of
r0.4 mm applies to all dimensions.
The tolerance for multiple connection is
r(number of units x 0.4) mm.
Stopper Pins
1.2 dia.
2.4 dia.
0.4
2.7
Note: 1. Two pins constitute one set.
2. The first shipment is free and is attached
to the Switch.
Order the A7BS-S separately if it is
required for maintenance.
0
8
1
6
3
7
24
3
5
1
2
3
4
5
6
7
8
9
10
Size C
Pin insertion position (2)
0
8
Size A
Size B
(n x 8 + 8) (n x 8 + 6)
2
2.6
5
4
Pin insertion position (1)
Ten, 1.2 dia.
(Unit: mm)
A7BL-206(-1)
A7BL-207(-1)
Solder Terminals,
Locking Models
6.1
8±0.1
A
2.8
24
15.4
Number of
Switches
(n)
*
24.5
20.6 22
2
Solder terminal
When setting
Panel thickness: 1 to 3
3.6
* If the output code is 06, the dimension is 32.5;
if the output code is 07, the dimension is 43.5.
Panel Cutout
22.4+0.4
0
3
6.9
0.8
B
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P=8±0.2
C+00.3
1
2
3
4
5
6
7
8
9
10
Size A
Size B
(n x 8 + 8) (n x 8 + 6)
16
24
32
40
48
56
64
72
80
88
Size C
14
22
30
38
46
54
62
70
78
86
14.4
22.4
30.4
38.4
46.8
54.8
62.8
70.8
78.8
86.8
Note: 1. The dimensions above include both End
Caps, and will increase 8 mm for each
Spacer inserted.
2. Unless otherwise specified, a tolerance of
r0.4 mm applies to all dimensions.
The tolerance for multiple connection is
r(number of units x 0.4) mm.
(c)Copyright OMRON Corporation 2007 All Rights Reserved.
3
A7BS/A7BL
Accessories (Order Separately)
End Caps for Push-operated Switches
A7B-M(-1) Snap-in Panel Mounting
Left Side
Right Side
(30)
24
3.2
2.8
4
4
(30)
24
2.8
3.2
24.5
24.5
2.4
22
(3.5)
3
3
(3.5)
3
22
Spacers for Push-operated Switches
A7B-P@(-1) Snap-in Panel Mounting
24
2.8
3
22
24.5
8±0.1
The @ in the Spacer model number stands for a letter in the range A to U. (Refer to the table under the explanation about Spacers on page 2.)
Note: Unless otherwise indicated, dimensional tolerances for dimensions in the models above are ± 0.4 mm.
Connectors (These devices allow Switches to be quickly removed for maintenance and inspection of connectivity, and quickly re-installed.)
A7B-C
Solder Terminals
37
31
24
21
3.3 dia.
7.8
Inserting Connectors
UP
9
20.5
P=2.54
1
3
2
3
7
5
4
Insert Connectors with the "UP" arrow
pointing up.
13.5
6
22
A7B-CP
PCB Terminals
24
21
7.8
UP
9
17.5
Connector
13.5
0.6 x 0.6
3
P = 2.54
1
3
2
7
5
4
6
22
Note: Unless otherwise indicated, dimensional tolerances for dimensions in the models above are ± 0.4 mm.
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4
A7BS/A7BL
Output Codes/Terminals
x Switches with output codes 06 or 07 both use binary coded decimal
but Switches with output code 07 have a component-adding
provision. Similarly, Switches with output codes 54 or 55 both use
binary coded hexadecimal but Switches with output code 55 have
a component-adding provision.
Output code
number
x How to Read Output Codes
For example, when the dial position is "3," the common terminal C
on the Switch is connected to terminals 1 and 2. When the Switch
is inserted into the Connector, the common terminal C becomes
connector terminal 2, and terminals 1 and 2 become connector
terminals 4 and 5 respectively.
Terminals
Output codes
Model
06
06
07
Fourteen,
1-dia. holes
Dial
07
Switch Unit or Common terConnector
minal number
Switch Unit
C
Connector
2
Connector
1
0
1
2
3
4
5
6
7
8
9
Terminals connected to
common
1
2
4
8
4
5
6
7
4
5
6
7
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
Note: The solid dot ● indicates that the internal switch is ON
(i.e., connected to the common terminal).
Twenty-eight,
1-dia. holes
Component-adding provision
Dial
1.3
9
19
Nineteen,
1-dia. holes
8
7
6
5
4
3
2
1
15
8
6
4
P=3.6
2
0
15
2.5
2.5
2.5
20.6
0
1
2
3
4
5
6
7
8
9
0
●
1
Terminal connected to common
2
3
4
5
6
7
8
9
●
●
●
●
●
●
●
●
●
Note: The solid dot ● indicates that the internal switch is ON
(i.e., connected to the common terminal).
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5
A7BS/A7BL
Output code
number
Terminals
Output codes
Model
54
55
54
Fourteen,
1-dia. holes
Dial
55
Twenty-eight,
1-dia. holes
Component-adding provision
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Switch Unit or Common terConnector
minal number
Switch Unit
C
Connector
2
Connector
1
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
Terminals connected to
common
1
2
4
8
4
5
6
7
4
5
6
7
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
Note: 1. The solid dot ● indicates that the internal switch is ON
(i.e., connected to the common terminal).
(c)Copyright OMRON Corporation 2007 All Rights Reserved.
6
A7BS/A7BL
Ordering Procedure
Place orders as shown in the example below, specifying the model
and number. Standard products are not factory-assembled for
shipment. Contact your OMRON representative for details on
ordering factory-assembled sets.
4
1.
2.
3.
4.
1
3
2
4
A7BS-206 (Switch Unit): 2 pieces
A7BS-207 (Switch Unit): 2 pieces
A7B-PA (Spacer): 1 piece
A7B-M (End Caps): 1 pair
Safety Precautions
Refer to Precautions for Correct Use in the Technical Guide for Thumbwheel Switches.
Precautions for Correct Use
Models with External Stoppers (A7BS-20@-S)
Handling
• The molded components of the Switch use polyacetal resin and
ABS resin. It is recommended that alcohol is used to wipe off dirt
and smudges from the molded components. Take care to prevent
the alcohol from getting inside.
• A7B Thumbwheel Switches are not drip-proof. Do not use them in
areas subject to water or oil exposure.
• Do not allow solder flux or alcohol to enter the Switch.
With the A7BS-20@-S, any range can be set externally using the
Stopper Pin. Insert the Stopper Pin using the following procedure:
(3) Stopper Pin (upper limit)
(2) Stopper Pin (lower limit)
(1) Display window
Setting Numbers
Locking Type
• Set with the setting button by raising it.
• Return the button to its original position after setting. It is then
locked to prevent rotation, and the set numbers will not change
accidentally.
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Example: To Display the Range 0 to 7
1. Any number within the range of (0 to 7) can be chosen to limit the
numbers displayed in the display window. (In this example, 8 and
9 are outside of this range.)
2. First, insert the Stopper Pin in the hole
in front of the lower limit ("0") for the
number to be defined.
3. Next, inset the Stopper Pin in the hole
past the upper limit ("7") for the number
to be defined. (The Stopper Pins then
surround the exact range to be
defined.)
4. Confirm that the (+) push-button can no
longer be pushed after reaching the
upper limit of ("7").
5. Confirm that the (-) push-button can no longer be pushed after
reaching the lower limit of ("0"). This completes the setting.
(c)Copyright OMRON Corporation 2007 All Rights Reserved.
7
Safety Precautions for All Thumbwheel Switches
For precautionary information on individual products, refer to Safety Precautions in the relevant section.
WARNING
Electric shock may possibly occur. Do not perform
wiring work or touch the charged parts of terminals
while power is supplied to the Switch.
Precautions for Correct Use
For details, refer to Precautions for Correct Use of Thumbwheel
Switches in Technical Guide for Switches and Level Control
Equipment.
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C-1
Technical Guide for Thumbwheel Switches
Precautions for Correct Use
Environment
Models with PCB Terminals
x Do not use where gases are generated (ammonia, chlorine, sulfur
dioxide).
x Although Switches are of nearly dust-proof construction, they are
not drip-proof, therefore do not use in areas subject to water or oil
exposure and do not operate with wet or oily hands. (The A7MD
has a dust-proof construction on contact parts, but consider your
installation location carefully. The A7MA is not of dust-proof
construction.)
x Provide additional dust-proofing measures, such as using a dustproof cover, when using in sand-exposed areas.
Storage
Do not store Switches in areas subject to high temperature or high
humidity, or store them in room-temperature areas for extended
periods of time. Doing so may cause oxidation of the terminals or
problems with solder. It is also recommended that long periods of
storage be avoided in general.
Handling
x Wiring
After wiring has been completed, ensure an appropriate insulation
distance.
x Set-up
Do not use the Switch in the normally-pressed state. Doing so may
occasionally result in premature deterioration of parts and changes
in the characteristics.
x Do not touch charged parts, such as terminals, while the power is
ON.
x Do not connect more than one power supply to a single Switch.
Doing so may result in circuit malfunctions and short-circuits.
x When changing settings, do not touch the operating buttons if your
fingers are wet or there is oil or any other foreign substance on your
fingers.
x It is recommended that alcohol is used to wipe off dirt and smudges
from the molded-plastic cases. Take care to prevent the alcohol
from getting inside.
x Do not use thinner or other solutions which might damage the
plastic.
x When connecting Switches, fit the mating parts together.
x When separating Switches, use a screwdriver as shown in the
figure below; disconnect them by releasing the top and bottom
hooks. Be careful not to bend the hooks.
x When using models with PCB terminals, make the terminal
insertion holes in the back board (mother board) 1 mm or larger in
diameter.
x Do not use excessive force in handling models with PCB terminals.
In particular, take care to avoid dropping them as the terminals
might bend or break.
Reference: Terminals can withstand a force of
7.84 N for 1 minute or more (A7D: 4.9
N for 10 seconds or more), and survive
bending of 20q without breaking after
returning to original position.
Withstanding the repetitive application
of external pressure, however, is
beyond the scope of Switch
specifications.
Connectors
x Insert Connectors while keeping the arrow pointing up (refer to
A7BS/A7BL and A7PS/A7PH for details).
x Connector insertion load is about 14.7 N for each A7B-C and 34.3
N for each NRT-C.
Soldering
Note the following points when soldering printed circuit boards:
x Automatic Soldering
Do not use dip cleaning. Doing so may result in flux penetration of
the Switch interior, causing contact and rotational defects. Clean
the flux as shown in Figure 1, tilting the Switch 80q or less and using
a brush to apply the solvent only to the back of the board. It may
also be cleaned by dipping only the back of the board into the
solvent and then using a brush to clean.
x Dip Soldering
When applying flux solvent, the dipping time is a maximum of 2
seconds. As shown in Figure 2, avoid flooding the top surface of the
printed circuit board with flux. Using a brush to apply flux further
reduces the danger of flux penetration. When cleaning flux with a
brush, tilt the Switch 80q or less, as shown in Figure 1, in order to
prevent flux from flowing onto the switch mounting surface. Clean
flux as described above under Automatic Soldering.
Figure 1
Figure 2
Top surface
of board
Back surface
of board
80° or less
x Do not push the (+) and (-) operating push-buttons at the same
time.
x Do not drop the Switch. Doing so may possibly result in deformation
of the terminals, damage to the PCB, or damage to the resin catch
(for connecting) on the side of the Switch.
x The output may be unstable while the pushbuttons are being
pressed due to the structure of the Thumbwheel Switch. Read the
output signal only after the display has stopped moving.
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Wipe away flux
with a brush.
x Using a Soldering Iron
Use a 30-W soldering iron at a temperature of 350qC for a
maximum of 3 seconds, and flush as described above.
Do not apply force to the terminals during soldering and for 3
minutes after soldering is completed. Doing so may result in
conduction or operation failure.
x Ensure that soldering flux and alcohol do not penetrate into the
Switch interior
(c)Copyright OMRON Corporation 2007 All Rights Reserved.
C-2
Read and Understand This Catalog
Please read and understand this catalog before purchasing the products. Please consult your OMRON representative if you have any questions or
comments.
Warranty and Limitations of Liability
WARRANTY
OMRON's exclusive warranty is that the products are free from defects in materials and workmanship for a period of one year (or other period if
specified) from date of sale by OMRON.
OMRON MAKES NO WARRANTY OR REPRESENTATION, EXPRESS OR IMPLIED, REGARDING NON-INFRINGEMENT, MERCHANTABILITY, OR
FITNESS FOR PARTICULAR PURPOSE OF THE PRODUCTS. ANY BUYER OR USER ACKNOWLEDGES THAT THE BUYER OR USER ALONE
HAS DETERMINED THAT THE PRODUCTS WILL SUITABLY MEET THE REQUIREMENTS OF THEIR INTENDED USE. OMRON DISCLAIMS ALL
OTHER WARRANTIES, EXPRESS OR IMPLIED.
LIMITATIONS OF LIABILITY
OMRON SHALL NOT BE RESPONSIBLE FOR SPECIAL, INDIRECT, OR CONSEQUENTIAL DAMAGES, LOSS OF PROFITS, OR COMMERCIAL
LOSS IN ANY WAY CONNECTED WITH THE PRODUCTS, WHETHER SUCH CLAIM IS BASED ON CONTRACT, WARRANTY, NEGLIGENCE, OR
STRICT LIABILITY.
In no event shall responsibility of OMRON for any act exceed the individual price of the product on which liability is asserted.
IN NO EVENT SHALL OMRON BE RESPONSIBLE FOR WARRANTY, REPAIR, OR OTHER CLAIMS REGARDING THE PRODUCTS UNLESS
OMRON'S ANALYSIS CONFIRMS THAT THE PRODUCTS WERE PROPERLY HANDLED, STORED, INSTALLED, AND MAINTAINED AND NOT
SUBJECT TO CONTAMINATION, ABUSE, MISUSE, OR INAPPROPRIATE MODIFICATION OR REPAIR.
Application Considerations
SUITABILITY FOR USE
OMRON shall not be responsible for conformity with any standards, codes, or regulations that apply to the combination of products in the customer's
application or use of the product.
At the customer's request, OMRON will provide applicable third party certification documents identifying ratings and limitations of use that apply to the
products. This information by itself is not sufficient for a complete determination of the suitability of the products in combination with the end product,
machine, system, or other application or use.
The following are some examples of applications for which particular attention must be given. This is not intended to be an exhaustive list of all possible
uses of the products, nor is it intended to imply that the uses listed may be suitable for the products:
• Outdoor use, uses involving potential chemical contamination or electrical interference, or conditions or uses not described in this catalog.
• Nuclear energy control systems, combustion systems, railroad systems, aviation systems, medical equipment, amusement machines, vehicles, safety
equipment, and installations subject to separate industry or government regulations.
• Systems, machines, and equipment that could present a risk to life or property.
Please know and observe all prohibitions of use applicable to the products.
NEVER USE THE PRODUCTS FOR AN APPLICATION INVOLVING SERIOUS RISK TO LIFE OR PROPERTY WITHOUT ENSURING THAT THE
SYSTEM AS A WHOLE HAS BEEN DESIGNED TO ADDRESS THE RISKS, AND THAT THE OMRON PRODUCT IS PROPERLY RATED AND
INSTALLED FOR THE INTENDED USE WITHIN THE OVERALL EQUIPMENT OR SYSTEM.
Disclaimers
CHANGE IN SPECIFICATIONS
Product specifications and accessories may be changed at any time based on improvements and other reasons.
It is our practice to change model numbers when published ratings or features are changed, or when significant construction changes are made.
However, some specifications of the product may be changed without any notice. When in doubt, special model numbers may be assigned to fix
or establish key specifications for your application on your request. Please consult with your OMRON representative at any time to confirm actual
specifications of purchased product.
DIMENSIONS AND WEIGHTS
Dimensions and weights are nominal and are not to be used for manufacturing purposes, even when tolerances are shown.
ERRORS AND OMISSIONS
The information in this catalog has been carefully checked and is believed to be accurate; however, no responsibility is assumed for clerical,
typographical, or proofreading errors, or omissions.
PERFORMANCE DATA
Performance data given in this catalog is provided as a guide for the user in determining suitability and does not constitute a warranty. It may represent
the result of OMRON’s test conditions, and the users must correlate it to actual application requirements. Actual performance is subject to the OMRON
Warranty and Limitations of Liability.
PROGRAMMABLE PRODUCTS
OMRON shall not be responsible for the user's programming of a programmable product, or any consequence thereof.
COPYRIGHT AND COPY PERMISSION
This catalog shall not be copied for sales or promotions without permission.
This catalog is protected by copyright and is intended solely for use in conjunction with the product. Please notify us before copying or reproducing this
catalog in any manner, for any other purpose. If copying or transmitting this catalog to another, please copy or transmit it in its entirety.
2007. 10
OMRON Corporation
In the interest of product improvement, specifications are subject to change without notice.
Industrial Automation Company
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(c)Copyright OMRON Corporation 2007 All Rights Reserved.
Mouser Electronics
Authorized Distributor
Click to View Pricing, Inventory, Delivery & Lifecycle Information:
Omron:
A7BS-206 A7BS-254-1 A7B-CP A7B-PA-1 A7B-M-1 A7BS-206-S-1 A7BS-206-1 A7BS-207-S-1 A7BS-207-1
A7BS-206-S A7B-C A7BL-206 A7BL-206-1 A7BL-206-PM A7BL-206-PM-1 A7BL-207 A7BL-207-1 A7B-M A7BPA A7B-PU A7B-PU-1 A7BS-203 A7BS-203-1 A7BS-206-PM A7BS-206-PM-1 A7BS-206-S04 A7BS-207 A7BS207-PM A7BS-207-PM-1 A7BS-207-S A7BS-207-S05-1 A7BS-219 A7BS-219-1 A7BS-254 A7BS-255 A7BS-255-1
A7BS-256 A7BS-S A7BL-206-S09-1 A7BS-207-D