About this 3D model

A small parametric shelf. The dimensions can be entered in the variables in the onshape design . It's not very sturdy, but it should be able to hold small weights. This version is not stackable. Improved version with better stability, using the suggestion by @BikeCyclist . I used ABS with 4 walls with 25% infill and no supports, but I think 3 walls and 20% would be enough.