Compare SMC IDF-BP316 Refrigerated Air Dryer, Idf, Idfb MSRP: Now: $227.90 Was: IDF/IDU, Bypass Piping SetIDF refrigerated air dryer series, in compliance with the Montreal Protocol Regulations, uses refrigerants R134a and R407C to prevent any damage to the earth s ozone layer. (Medium size series use R22). Series IDF can... MSRP: Now: $227.90 Was: Compare