R1234YF Conversion Kit with Manual Couplers. Includes: (1) Brass High Side Manual Coupler with M12 fitting, (1) Brass Low Side Manual Coupler with M12 fitting, (2) fittings (M12 x 1/4" SAE) to connect the High and Low side manual couplers to 1/4" R12 hoses and (2) fittings (M12 x M14) to connect the High and Low side manual couplers to M14 R134a hoses.