Since the cellular model of the iPad isn’t subject to typically two-year contracts, users have always been free to start or end pre-paid cellular data plans at will from the device’s settings. In the past, however, this meant buying your iPad from one carrier and being locked into that carrier’s plans.

With tomorrow’s launch of the iPad Air 2, however, Apple is changing that by including its own SIM card with each unit. This SIM card will work with multiple US carriers—AT&T, Sprint, and T-Mobile—and allow users to not only enable or disable a cellular plan as they see fit, but also switch back and forth between carriers to find the plan that works best for them at the moment.

For some reason, Verizon isn’t supported on the Apple SIM, which brings into question how the carrier will be supported at all. Sprint, which uses CDMA technology like Verizon, is compatible with the new SIM, so it’s quite curious that Verizon doesn’t appear on the list. It’s possible that Verizon just wouldn’t get on board with the Apple SIM idea and will require users to get a SIM from them instead.

The iPad Air 2 goes on sale tomorrow. The mostly-unchanged iPad mini 3 will also ship with an Apple SIM.