Cat® Rubber O-Ring Seal for Housings and Oil Fillers. Cross Section Diameter (mm): 3.53. Inside Diameter (mm): 47.22. SAE AS568 Dash Size: -225. Material: FKM – Fluoroelastomer,FKM (75),FKM,Fluoroelastomer (FKM) Rubber. Material Description: FKM rubber is capable of service temperatures of -40 to 150C and is resistant to air, fuel (including bio-diesel), lubricants and oils. FKM rubber should not be used in applications that require resistance to water or coolant. Notes: Dimensions and material descriptions provided for reference only. Polymer: FKM (Fluorocarbon). Applications: High temperature applications requiring resistance to air, fuels, lubricants and hydraulic fluids. Not Compatible With: Amines; Brake fluids; Engine Coolant; Fire Resistant Fluids; Ketones; Steam; Water. Material Hardness: 75A. Temperature (°C): -40 – 175. Compatible With: Diester lubricants; Halogenated hydrocarbons (above 100 Deg. C); Highly resistant to compression set; Petroleum fluids; Phosphate ester fluids; Silicone fluids; Some acids. Dash Size: 225. Seal/O-Ring Type: Standard