The DN25 NBR seal is good oil resistance, wear resistance, aging resistance, elasticity, and is easy to install Fit for Tube Size: 1 inch; Outer Diameter: 39mm; Inner Diameter: 27mm; Thickness: 6mm Shore Hardness: 65A; Working Temperature Range: -15°C to 100°C (5°F to 212°F) The sealing gasket provides a bearing surface for fastener load distribution or is used as a spacer between components Mainly used in wrench type quick connector sealing in the chemical industry, metallurgy, machinery, electronics, electrical appliances, etc.