The XPID100 and XPID101 devices both use the same SIM card format, the Mini SIM 2FF form factor. Please see the image below to clearly identify the SIM card type.
The devices have been used on both LTE and 3G networks, both in the United States (T-Mobile, ATT, Verizon, Sprint) and internationally on various carriers. Carriers will often ask for the IMEI to get the device type, but if you just get a provisioned SIM card and install it as shown in this article on our knowledge base, it will function appropriately for you.