This fitted, hinged plastic box from American Tool Group would be worth buying even if it didnt come with hundreds of O-rings. And it does. Black nitrile O-rings sorted by size. O-rings that will stay in their places until you need them. The 407-piece set includes 32 sizes from 1/4" OD x 1/8" ID x 1/16" to 2-1/4" OD x 2" ID x 1/8". It includes the size you're going to need. At your fingertips. Insted of in aisle 12 at the home center.