Captain O-Ring Field Medic Color Coded Master Paintball Oring Kit - 21 Sizes 63 Orings O-rings are color coded by size, eliminating the headache of matching up sizes. This 63 piece Field Medic Kit contains 21 of the most common sized o-rings found in paintball equipment (3 of each size) Keep the o-rings on hand to replace seals in a variety of paintball equipment including your marker, to your air/CO2 tank, and other accessories requiring o-rings. Excellent for quick o-ring replacements on Azodin, Bob Long, BT, DLX, Dye, Eclipse, GOG, MacDev, Proto, Smart Parts, Spyder, Tiberius, Tippmann, and Valken Markers