T-Mobile wants their customers to get better service while they are inside their homes. To make this happen, the wireless carrier is offering a free device that will help subscribers achieve "full-bar" coverage indoors.

T-Mobile will offer the 4G LTE CellSpot mini-tower that will plug into the back of an at-home Internet router to provide up to 3,000 square feet of LTE coverage indoors, USAToday reports. T-Mobile announced the mini-tower on Monday and it will become available on Wednesday.

The 4G LTE CellSpot is a small device that is just 8.5 inches wide, 8.5 inches tall and 1.3 inch thick. T-Mobile says they are the first to offer a mini-tower in the U.S.

T-Mobile says the 4G LTE CellSpot will ensure customers have full bars of coverage when they are inside their homes. 

Post-paid T-Mobile customers have the opportunity to receive the 4G LTE CellSpot for free. They will be required to put down a $25 deposit and remain subscribed to T-Mobile. Customers will receive the devices in shipments instead of from stores.

T-Mobile says LTE data is usually faster and more reliable than Wi-Fi, so the 4G LTE CellSpot will perform better than Wi-Fi data. 

Last year, T-Mobile tried to improve indoor calling by offering a Wi-Fi router. This allowed customers to perform Wi-Fi calls when their cell service was weak.

T-Mobile believes the LTE mini-towers will work even better than the Wi-Fi routers. Customers will simply plug in the 4G LTE CellSpot to the back of their Internet router, and they will not be required to do anything more.

T-Mobile has an upcoming "Uncarrier" promotion on Nov. 10. There are speculations the wireless provider could announce customers will be able to use streaming services like Netflix and Hulu without it counting against their data.