Price between OBDSTAR X100 PRO C and D type are different,Why?

Lots of customers were looking for purchasing the OBDSTAR made X100 Pro auto key programmer. But they were confused the price among C, D and C+D type? So they contacted the obdstartool.com customer service and our sales girl help to make a comparison to help to find a good chioce
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OBDSTAR X100 PRO English version has 4 configurations
SK164 OBDSTAR X100 PRO C+D type:
IMMOBILISER+ OBD Software and Odometer Adjustment + OBD Software
SK164-B OBDSTAR X100 PRO C type:
IMMOBILISER+ OBD software
SK164-C OBDSTAR X100 PRO D type:
Odometer adjustment+ OBD software
Optional configuration (E): EEPROM adapter
(Note: IMMO function= program keys from vehicles’ immobilizer system)
Price differs because the function differs. Other features (hardware material, PCB, appearance, update, language etc) are the same.
SK164-C X100 Configuration D type (Odometer adjustment+ OBD software) does not come with 1pcs x HONDA-3 connector, 1pcs x HYUNDAI/KIA-10 connector and 1pcs x KIA-20 connector.
OBDSTAR X100 Pro key programmer vehicle coverage:
EEPROM Adapter: EEPROM ADAPTER V30.40
Immobilizer: ACURA, AUDI, BAIC, BESTURN, BRILLIANE, BYD, CHANGAN, CHANGHE, CHERY, CHRYSLER, CITROEN, DFLZ, DFPV, DS, FORD, GEELY, GM, GREATWALL, HAFEI, HAIMA, HAWTAI Motor, HONDA, HONGQI, HUAPU, HYUNDAI, INFINITI, JAC, JAGUAR, KIA, LANDROVER, LEXUS, LIFAN, LINCOLN, LUFENG, MAZDA, MG, MITSUBISHI, NISSAN, OPEL, PEUGEOT, PORSCHE, RENAULT, ROEWE, SAIC ENGLANG, SEAT, SKODA, SMART, SSANGYONG, SUBARU, SUZUKI, TOYOTA, VW, YOUNGLOTUS, ZZMAZDA, ZZNISSAN;
OBDII: OBDII V30.02 for diagnose
Odometer correction: AUDI, VW, BENZ, Chrysler, Ford, GM, Porsche, Skoda, Seat