The Retron-Sq is a small cube that plays your GameBoy / GameBoy Color and GameBoy Advance games on your TV.
Simply connect the console via HDMI to your TV, power it using a USB-C-Connector, plug in the (included) controller and start playing!
The firmware can be upgraded via MicroSD Card (you can download the latest version from this website)
It's based on VisualBoy Advanced, so the emulation is pretty accurate.
The Retron-Sq supports most GameBoy / GameBoy Color and GameBoy Advance games including battery backed up saves.
In the box:
* The Retron-Sq itself
* 3 feet (0.9m) long HDMI cable
* Controller with 10 feet (3m) long cable
* 6 feet (1.8m) long USB-C cable