ACDelco GM Original Equipment A/C Line O-Rings are used for forming a gas-tight connection between air conditioning components and are GM-recommended replacements for your vehicle’s original components. A/C O-Rings should be lubricated with Viscosity 525 mineral oil to prevent leaks and fitting corrosion. These original equipment A/C line O-Rings have been manufactured to fit your GM vehicle, providing the same performance, durability, and service life you expect from General Motors.