The stands for Updated . This is critical. The VAG ecosystem constantly evolves. A 2002 Golf uses a completely different encryption method than a 2015 Passat. The "UPD" version indicates that the programmer’s database and firmware have been refreshed to support the latest VAG MQB platforms and newer NEC MCUs.
Highly effective on Magneti Marelli and VDO dashboards commonly found in MK4 Golf, Bora, Passat B5.5, Audi A3/A4/A6/TT. vag eeprom programmer 119g skacat upd