This design protects the screen of your R36S Portable Retro Gaming Handheld from being damaged and blocks out excess light from reflecting off the glossy screen. It slides on and is held in place with two bumps that fall into the screw holes above the rear buttons controls. It holds on tight while giving you access to the power and volume buttons on the side. Triangles openings let you see if you have a microSD card in either side.