From the A/C Pro® professionals who specialize in do-it-yourself A/C recharge kits for cars and trucks, A/C PRO® Professional Grade Auto Air Conditiong Recharge & Retrofit Kit is a professional grade all-in-one kit for automtive A/C recharge. Easily bring back the cold air delivered from existing R-134a A/C systems or the retrofit kit converts older R-12 A/C systems to R-134a.