First Alert CO400B Carbon Monoxide Alarm, Removable Battery, CO Detector, Electrochemical 6926K75 Valve Function On Off Valve Type Valve Function On Off Valve Type Gate Actuation Manual Valve Operation Handle Handle Style Wheel Handle Type Standard Handle Material Iron Shape Straight Fitting Type Connector Connection Type Pipe Connection Style Threaded Pipe Size 1 2 Gender Female Thread Type NPT Flow Coefficient (Cv) 17 000 psi Pressure Range Type Pressure Nominal Dial Size 2 1 2 in Gauge Case Material 304 Stainless Steel Lens Material Polycarbonate Socket Material 316L Stainless Steel Sensor Material 316L Stainless Steel Sensor Type Bourdon Tube Movement Material 304 Stainless Steel Bezel Material 304 Stainless Steel Process Connection 1 4 in NPT Male Features Front Loading Battery Carbon Monoxide Alarm