12IN 1 USB 2.0 Card Reader/ Writer Flash & Sim Memroy

Mac users beware -- this product is not compatible. Sure, you can read a mass storage device (which is OS-agnostic), but you can do that with the reader that you get for free with your memory card. If you want to touch SIM cards at all, you're looking at Boot Camp or else you're out of luck. The marketing is pretty deceptive on this point, so watch out!

From the product's user guide:

b. For MAC OS, the combo device supports MAC OS version 9.0 and above through USB MASS STORAGE.
* SIM card reader doesn't support MAC OSBuy 12IN 1 USB 2.0 Card Reader/ Writer Flash & Sim Memroy!