Robinair 16009 134R DiscovR Refrigerant Identifier Best defense against unknown refrigerant and the risks associated with unknown refrigerant is a refrigerant identifier Contaminated refrigerant can wreak havoc on any R134a recovery recycle and recharge machine Protect your A/C service equipment and know whether or not you have acceptable R134a refrigerant before servicing the vehicle DiscovR refrigerant identifier notifies you when the system contains excessive air Pass and fail lights clearly show if refrigerant is pure enough to be recovered