Off with plunger depressed, spring return to On. For energizing two circuits simultaneously. 10A at 12V DC. 7/8" (22.2mm) long mounting stem, 7/16" (11.1mm) long, two flats on stem for mounting in double-D hole. Four screw terminals. Plunger 19/64" (7.54mm) long. Two hex nuts and one lock washer.