Shop for Electrical at The Home Depot. For nearly 85 years General Tools has grown to become the recognized industry leader for specialty hand tools and instruments. The PNG2000A Detects natural gas, compressed natural gas, ch4, methane, propane, butane, liquid natural gas (LNG), liquid petroleum gas (LPG) to locate leaks in pipes, valves and fittings. This essential tool is packed with features such as audible and visible annunciation and Catalytic combustion sensor. The high sensitivity of the unit to natural gas (methane) and LPG (propane) and affordability make it ideal for the technician, do-it-yourselfer or homeowner.