A blend of R-32, R-125, and R-134a that has very similar properties to R-22 in air conditioning equipment. R-407C has the closest property match to R-22 in an air conditioning retrofit project compared to other blends on the market. It can also be used in medium temp R-22 refrigeration systems. R-407C has a 10°F temperature glide. New systems built with R-407C must have POE lubricants, and retrofitted R-22 systems would need the residual oil flushed with POE.