Small hook/hanger that you can use to hang small objects off of a surface that self adjusts for a range of thicknesses. I haven't tested what range of thicknesses and depths it is compatible with yet nor have I tested the weight it can handle, but it was designed to be used with flat objects that are approximately 40mm thick and 32mm deep on the bottom like a tabletop or a shelf, and strength will depend on print settings and filament. The main issue I've run into with this so far is that if the edges of the surface you are attaching them to are filleted/rounded, the top arm struggles to hold on if it doesn't have a flat surface to contact with.