Ah, the tiny little box. Reminds me in size of the new Apple TV. Yay for cheapo silver paint. What do you expect for 20 dollars?

To open it, you must remove 3 screws. 1 on the back, and 2 on the bottom behind rubber stickies.

There is also 1 clip you must undo on the back, it's visible.

The device takes OTA digital signals and converts it into analogue 480p. Ironic that it's called Access "HD". Composite or coaxial are your choices here.