Read Panasonic KX-TG8421CAT / KX-TGA840UAT (serv.man2) Service Manual Supplement online
1.2. ORIGINAL AND NEW PARTS COMPARISON
TG8421CAT/KX-TGA840UAT, Order No.KM40903858CE.
*The following items (1-8) indicate the reason for change. See the “Notes” column for each part in ORIGINAL AND NEW PARTS
1. Improve performance
*o: EEPROM has been changed from 64 k to 128 k.
3. To meet approved specification
There is no change in the replacement parts list.