Recommended for petroleum-based hydraulic oils, water, glycol antifreeze solutions, engine lubricating oils, and air. Suitable for low-pressure cleaning and pneumatic systems, return lines and low pressure lines. Lock-On hose and couplings are not recommended for pressure surge or critical applications. Do not use for gasoline or diesel fuels, unless approved by Gates H/C Product Application. Recommended Couplings: Field Attachable LOL Couplings (Except -3), GLP Couplings (Except -3), GLX Couplings (-4, -6, -8, -12), Special Order Couplings May Be Needed (-3).