uxcell 10 Pcs Black Nitrile Rubber O Rings NBR Seal Washer Grommets 55mm x 5.7mm Product Name : Nitrile Rubber O Ring;Material : Nitrile Rubber (NBR) Inside Diameter : 43.6mm/1.72";Outside Diameter : 55mm/2.17" Thickness : 5.7mm/0.22";Color : Black Weight : 55g Package Content : 10 x Nitrile Rubber O Rings