Summary

A shelf for a desk. Each leg's height can be adjusted individually. All components thread or press-fit together. the legs are hollow inside and can acommodate a small stash of whatever you can think of, they are tall enough to fit rolled dollar bills. Height is adjustable from 10.5cm to 16cm. Optimized for a 220mm printbed (components are exactly 220mm in length)
5/26: added a center bracket so shelf can be expanded as big as you like