The Col-o-dex Rotary Cards feature the same 100lb/160gsm bright white paper that you've come to love in the Col-o-ring Ink Testing Books but its now die cut into larger 4”x2.625” sheets to fit into a standard rotary card files like a classic Rolodex®. Each pack features 100 cards, each shrink wrapped with our signature chipboard cover and backing cards. Don't forget to add a set of tabs to make your Col-o-dex complete!