Square D QO240 common trip, thermal magnetic; 2 pole; 120/240 vac at 50/60 hz (ul/csa); 40 ampere; interrupting rating 10 kiloampere; wire size 8 to 2 awg (aluminum/copper); plug on mounting; size 1.5 inch w x 2.91 inch d x 3 inch h; approval ul; used on load center