Small, thin lens cap, for lenses with 49mm and 52mm filter threads. (I'll probably add a 58mm version at some point)
Printed with a mix of PET and ABS. The PET makes a nicer spring, but it will work in ABS too (I haven't tried PLA).
Prints in a single piece. Some of the parts will probably be lightly fused together when it comes off the printer. You should be able to gently bend the lens cap, then pinch it closed, and that should snap all the connections that need to be separated.
If you want to change materials or colors, the spring section starts at 2.4mm, and the sliding section starts at 1.25-1.4mm.