Simple Parametric Tray

Recently I've had the need for trays of various sizes, and I seemed to remember parametric models where you could just add length, width and height and it would generate a tray. However, I couldn't find any of these.

So I whanged together a simple, parametric tray. Aside from rounded corners, possibly its only feature is a channel on the bottom to help prevent warping and lifting.

***Unfortunately*** this won't work in Thiniverse's Customizer since it uses BOSL2, and Customer doesn't use includes.