There are two versions of the One Pi Tower, the very easy version and the easy version. Here's the link to the very easy version step-by-step building instructions. This version is intended for people who don't have access to a table saw or a router. It uses pre cut 12" mdf boards (they're really 11-1/4"). The other version has more appealing dimensions because its depth is greater than its width. I have a pair upstairs somewhere and will measure them and post the dimensions.