Multipurpose adjustable stand

This is a 150mm stand with a hollow centre. I made it so I can part balance my laptop off a desk riser but it can be used for lots of other reasons. It is hollow so that a second part can slide inside to create any top part, such as a wider support or varying heights by making a shim, see example.

At 100% scale, the hollow is a 38mm diameter tube and a 37mm cylinder will fit inside.