Double pole, Triple wire, Non-Fusible Mechanical Interlock. 100 amp, 240 vac. 100A 2P 3W 250VAC N/F MECH INTERLOK Legrand-Pass & Seymour http://www.legrand.us/product-detail/PassAndSeymour/IEC-309-Products/Fusible-NonFusibleMechanicalInterlock/Non-Fusible-Mechanical-Interlock/100-Amp/PS3100MIR6W.