Dash Size (in): 278 Primary Sealing Material: Rubber Seal/O-Ring Type: Standard Cross Section Diameter (in): 0.139 Inside Diameter (in): 11.984 Outside Diameter (in): 12.262 Material: Nitrile (NBR) Material Description: Nitrile (NBR) rubber is capable of service temperatures of -40 to 100C and is resistant to fuel oils, gasoline, ultra low sulfur diesel fuel and lubricants. Nitrile rubber is not recommended for applications that require resistance to bio-diesel or coolant. Hardness (Shore A): 75 SAE AS568 Dash Size: -278 Coating: None Color: Black Color Notes: Actual o-ring color may differ from image. Notes: Dimensions and material descriptions provided for reference only.