Mix ratio inserts assist in the measuring process with 3M™ PPS™ (Legacy) paint preparation system. Inserts have mix ratio printed on film insert for generic paint mixes. For use with the 6 fl oz cup. Used with 1:1, 2:1:1, 3:1:1, 4:1:1, 5:1:1 and 6:1:1 ratios and 3M Tri-Scale, scalers 1-11. Tip: Film inserts must be placed between the hard cup and flexible liner. This complete painting system allows the painter to measure, mix, filter, and spray paint materials.