T-Mobile has partnered with SpaceX’s Starlink to extend service to ‘dead zones’ that cell towers can’t reach, and it’s asking people to participate in a free test run. T-Mobile has launched a wide-scale beta satellite-to-cell service using SpaceX’s Starlink,

The beta phase will run until July. Afterward, you can decide if you want to pay for the service.

T-Mobile Starlink is obviously available to T-Mobile customers, but the carrier said that Verizon and AT&T customers can also use it on their existing phones without switching entirely to T-Mobile. Verizon and AT&T customers will need an unlocked phone with eSIM technology, which lets users activate a cellular plan without a physical SIM card.