The SniffIT X1 from Nolek Inc., Plympton, MA, is a handheld leak detector for both helium and hydrogen. Weighing <300 g, and offering 10 hr. of battery life, the device has a response time <0.1 s, recovery time <1 s, 1 × 10–6 mbar.l/s sensitivity to hydrogen and 2 × 10–6 mbar.l/s sensitivity to helium. Recommended concentration and mixture is 5%–100% for helium and 5% hydrogen and 95% nitrogen for hydrogen. Because the device is sensitive to both helium and hydrogen, it can detect leaks independent of the tracer gas used for leak detection. An LED bar changes color depending on the leak rate detected.