Provides trouble-free changeover of power between shore power and generator. It is engineered for safe, reliable performance, and the unit's DC coiled relay prevents AC 'Chatter' noise and drop-out in low-voltage conditions. Accidental coupling of power to or from the shore line and generator is prevented by a 'break before make' configuration. T30 can be installed onto the back of WFCO 8900 Series Power Centers. Input : 120 VAC, 60 HzDimensions : 5"W x 5.625"H x 5"DWeight : 4.25 lbs