uxcell Black 40mm x 3.5mm O Rings Hole Sealing Gasket Washer 10 Pcs Product Name : O Ring;Material : Nitrile Rubber(NBR) Outside Diameter : 40mm / 1.57";Inner Diameter : 33mm / 1.3" Thickness : 3.5mm/ 0.14";Color : Black Weight : 10g Package Content : 10 x NBR O Ring