... tight high performance barrels - model: GB3020W, 0.20g, 5.95+/-0.015mm, white; 4000 Rounds/Bag, 20Bags/Carton ... Rounds/Bag, 20Bags/Carton- model: GB4020BK, 0.20g, 5.95+/-0.01mm, black; 4000 Rounds/Bag, 20Bags/ ... Carton- model: GB4020GR, 0.20g, 5.95+/-0.01mm, green; 4000 Rounds/Bag, 20Bags/Carton ... 6mm airsoft BBs, include 0.12g,0.20g,0.23g,0.25g,0.28g,0.30g,0.32g,0.36g and BIO-BB series ...