This Dorman value pack assorted o-ring set contains 407 pieces. This is the best value for this quality product. Never run to the store for an emergency purchase. This set contains all o-ring sizes R-01, R-02, R-03, R-04, R-05, R-06, R-07, R-08, R-09, R-10,R-11, R-12, R-13, R-14, R-15, R-16, R-17, R-18, R-19, R-20, R-21, R-22, R-23, R-24, R-25, R-26, R-27, R-28, R-29, R-30, R-31, R-32. Best value around with a quantity of 10 to 20 per size. These o-rings are high quality nitrile, professional grade.