These are the same K Cups included in our 9″ Aluminum 7075 Tube Solvent Trap Kits. Our K Cups are included with your original purchase of the 9” Aluminum Solvent Trap Kit, which includes 8 Stainless Steel K Cups. This kit is a very popular firearms cleaning option.
One reason the K Cups are popular is because the K shape allows for the base of the cup to sit on a flat surface, like a drinking glass. This allows for solvent that is trapped to not spill out of the cups as you remove them, or during transport when pouring solvent into the cups.