Black Rubber O Ring 4mm NBR 70 Sealing Ring Gasket

1 - The material selection of o ring Material: NBR, FKM, EPDM, VMQ, FFKM, FFKM, CR etc. 2 - The hardness selection of o ring The hardness of o ring is related to the pressure. The normal hardness is 70 shore a and the anti pressure property is 10mpa. 80 shore a is 15mpa. 90 shore a is 25mpa. Other hardness are also available. 3 - The size selection of o ring Measure the ID and C/S and inform us so we can offer the price to you.