Xi5-P allows you to put XFINITY TV anywhere in your home via WiFi, without a a cable connection. Powered by USB-C and connects to TV via HDMI. Supports High Dynamic Range (HDR), but not 4K/UltraHD, that will come in a future device.
Requirements: "To have a Wireless TV box in your home, you'll need XFINITY TV service, at least one additional X1 TV box to act as the primary X1 device on your account and XFINITY Internet with a Wireless Gateway 3 (with RDK-B firmware) to stream video over the Xi5's WiFi connection."
Update: This mini box currently has a $9.95 monthly charge.
Xi5 TV Box FAQ