Features: • Detects all refrigerant and blends -R12, R22, R502, R123, R134a • 18" Flex probe with exclusive patented Ion-Pump® advanced corona discharge technology sensor. • Ten sensitivity levels • Visual and audible leak location and intensity indicators • Patented selective Water Vapor Filter allows operation in damp enviroments and checking evaporator leaks • Exceeds SAE J1627 moving probe specifications • Made in the U.S.A. • 2 year manufacturer's warranty Sensitivity: With today's rapid introduction of new refrigerants, only the LS790B allows you the flexibility of 10 discrete sensitivity settings. Simply depress the sensitivity key and watch as the bar graph display moves from left to right (left being the lowest sensitivity setting and right being the highest). Over 100 computer generated tones and an active I0 LED visual bar graph display quickly alerts you to varying refrigerant concentration levels during leak testing. NOTE: At the lowest sensitivity setting, the LS790B can detect a CFC leak as small as 1/4oz/8g per year and an HFC leak, as small as 1/2oz/1.5g per year. LOCK-OUT(tm): The LS79OB's unique Lock-Out(tm) feature completely eliminates the effects of nuisance background contamination during the leak testing process. This is accomplished with the help of the LS79OA's advanced microprocessor, which will automatically and systematically store the recorded values of the surrounding refrigerant concentration levels, alarming only in the area of the highest recorded concentration level (the leak source).