SEMICONDUCTOR BF421 MARKING SPECIFICATION TO-92 PACKAGE 1. Marking method Laser Marking 816 1 2 K BF421 2. Marking 3 4 No. Item Marking Description KEC K KEC CORPORATION Lot No. 816 Device Name hFE Grade 2005. 4. 18 Revision No : 0 BF421 8 Year 0~9 : 2000~2009 16 Week 16 : 16th Week BF421 - 1/1