Abstract: To be used in a gas supply line having an upstream main on/off valve, a meter downstream of the valve, and a pressure regulator intermediate of the valve and meter, the gas supply line being used to supply gas to appliances at an installation site, a gas leak detection test station including a fitting connected in fluid communication with the line downstream of the pressure regulator, fitting having a body with a main inlet opening, a main outlet opening, and a flow path between the openings. The station further having a fixed valve body portion integrally formed with the body of the fitting, the fixed valve body having a movable valve portion which is movable between a normal valve closed position and a valve open position, the movable valve portion normally being urged towards the normal closed position, the body portion being adapted for connection with a manometer.