Features and Benefits: Robinair VacuMaster vacuum pump features below. 2-stage rotary vane design: Powerful, quiet high vacuum capability for maximum moisture removal and reduced evacuation time; Angled oil drain valve: faster, more complete draining; Top oil fill port: Better access when refilling oil; Cast aluminum body: Lightweight and durable die-cast aluminum reduces weight and creates a strong, durable pump; Quality: Performance-tested to meet Robinairs quality, durability and longevity standards; Intake screen: Prevents foreign matter from entering pumping chamber. In other locations, see your Robinair distributor; Multi-use: Designed for use on A/C-R systems using CFCs, HCFCs, and HFCs in conjunction with mineral oil, ester oil, alkyl benzene oil, and PAG oil as lubricants; Not for use with ammonia or lithium bromide systems; Not for use with A4L or other flammable refrigerants.