What kind of SIM are these?
All 6 pin or 8 pin have the SIMs have same functions.

At first we need to understand SIM Pinouts;

6 pin includes VCC, GND, I/O, VPP, RST, CLK

8 pin includes VCC, GND, I/O, VPP, RST, CLK, SIM_PRESENCE, GND

VCC is supply pin, 
GND is common ground pin, 
CLK is Clock pin, 
RST is Reset Pin and 
I/O pin is for Data transmission.

The only difference between 6 pin and 8 pin is of SIM_Presence pin, The is an optional pin of SIM, and their are two GND pins on 8-pin sim.

For you device you may use 6 or 8 pin SIM, as SIM_PRESENCE is not necessary required.

The only useable PINs for devices are VCC, GND, I/O, RST, CLK. Hope this will may help you