Detects organic vapors up to 50,000 ppm. Ergonomic, user-friendly and light-weight. The unit has an internal battery, samling pump and the fuel supply is also in the instrument module, itself. The fuel cylinder is refillable. This unit is well-suited for environmental, industrial and emergency-response applications. This unit requires 100% hydrogen gas as fuel for the flame. MSR can supply up to 8 hrs of operational fuel. It is strongly recommended that the hydrogen be acquired at the job site, if possible. The shipment of hazardous gases, such as hydrogen, is costly. AJAX can supply a mother tank for hydrogen.