Speedy PPS Cup Cap

I use GPI's Speedy PPS Cups for my LVLP/HVLP paint spray system, but I find the caps can be pretty fragile. Often the little grabby points break off, which makes them very annoying to remove from the cups with gloves on. 3 walls for strength, PETG is probably best for flexibility but any material will work so long as its resistant to the material in the cup (solvent based finishes may need something else? I use acrylic) Fusion 360 file included Here is an example of how the OEM caps break