TOOGOO(R) 50mm x 5mm Nitrile Rubber O Ring NBR Oil Sealing Gasket 10 Pcs Product Name : O Ring;Material : Nitrile Rubber(NBR) Outside Diameter : 50mm / 1.97";Inner Diameter : 40mm / 1.57" Thickness : 5mm/ 0.197";Color : Black Weight : 35g Package Content : 10 x O Ring