This is a cup holder for the plastic adirondack style chairs that you can get from Home Depot. Unfortunately they do not have a cup holder. This is sized for a soda/beer/bottle.
There are 2 versions here, version 2 is the one shown in the picture, version 3 is a sturdier design, however it uses a little more material.
Cup_Holder_Rev_002.stl | 43.3KB | |
Cup_Holder_Rev_003.stl | 123.1KB |