FluidMaster Flush 'N Sparkle Refill Cap

Don't throw away those FluidMaster Flush 'n Sparkle cartridges when you can add this easy to print removable cap (and liner) and refill them for much less cost than new ones. Less plastic waste for the landfills. 1 inch tablets (like the originals) fit nicely. Just carefully pull out the OEM cap and replace with the 3D printed slotted liner and simple twist on cap. Once refilled use right away or store replacements in zip-lock bags until needed. Be sure to print with chlorine resistant plastics such as PETG or ABS (not PLA).

Cura was a great tool for printing the necessary supports for the slots within the adapter ring. Some other slicer programs can be far too aggressive in generating unnecessary support structures.