Designed to repair minor leaks in the evaporator, condenser, connecting fittings and metal lines. R1234YF Max Seal was designed to save the consumer the burden of costly repairs in the form of replacement parts and expensive service labor. R1234YF Max Seal can be used in all R1234YF air-conditioning systems. The 3 ounce aerosol can contains enough R1234YF Max Seal to repair small leaks in 3 or 4lb a/c systems. IMPORTANT! - These cans have an R134a thread and will require an R134a Can to R1234YF Port can tap. We have these available for purchase. IMPORTANT: These cans are R134 can tap threaded (right hand thread) A R1234YF can tap will not work on this can and we suggest using ZeroR R134a Can to R1234YF Port Can Tap with Gauge