BEnviro-Safe R-134a R12 R22 Stop Leak, Stops O-Ring and Seal Leaks, 1 4oz Can ReviewbP PP Enviro-Safe R-134a R12 R22 Stop Leak, Stops O-Ring and Seal Leaks, 1 4oz Can PFor O-Rings & Seals OnlyPThe 3 ounce aerosol can contains enough Stop Leak to repair o-rings in 3 or 4lb ac systems.