A:AnswerThis unit is NOT 8" wide. Just look at the photo. You can clearly see the unit is wider than it is deep.
The specs do say it's 8" wide and depth is 13". (DEPTH is front edge to back). The specs are wrong. But it's easy to figure out that it's supposed to be 13" W x 8" deep.
A:AnswerYes, you can hang this shelf horizontally but it would not be very functional. It also weighs 20lbs empty. That's a lot of weight to hang on a wall.