Remote Gas Sensor for Scentry III GFRAB Gas Shut Off S ystem Purchase Separ ately Add up to 4 remote explosive gas detector gas sensors to Scentry III GFRAB Propane/Natural Gas Home Gas Detector not included . Explosive gas detector interfaces with the GFRAB to improve home safety when you cook or heat with natural gas or propane gas. Scentry III Remote Gas Sensor Specifications include a gray ABS plastic case, 4.6 x 3.1 inches that weighs 1/2 lb. Power consumption is 1.25 va with screw terminal connections and an output power of 9-24VDC. This unit has a manual reset and uses a tin dioxide semi-conductor sensor type. Alarm points for propane lp gas 5200 PPM and a Natural Gas/Methane alarm point of 12,000 PPM. The alarm signal output is an open collector type. The unit connects to the gas valve and controller via 4 conductor thermostat wire not included Made in USA. This item ships from a separate warehouse and may require extra time for delivery.