If you have a GBC Pronto ProClick binding machine, then you'll need to stock up on the Pronto ProClick cartridges! We have them in the standard four colors for ProClick spines, which includes white, black, navy blue, and frosted. Each color has two to three sizes available in 100 packs, which can hold anywhere from 20 to 100 sheets of 20lb paper. Getting cartridges allows for high density binding. We also offer zipper tools and kits, for easy binding. And to make your life easier, we sell pre-punched paper for your ProClick spines.