Kupczyk AC-DUAL A/C Service Station (R134a + R1234yf) Kupczyk AC-DUAL is a professional, fully automatic A/C service station designed for workshops aiming to service all vehicle types without limitations. Supporting two refrigerants — R134a and R1234yf — the unit seamlessly handles both older and modern air conditioning systems. An ideal solution for automotive services looking to expand their customer base, optimize workshop floor space, and work faster without investing in two separate machine