Triple pole, Four wire, Non-Fusible Mechanical Interlock. 380/440 vac. 30/32A 3P4W 380/440V MECHANICA INT Legrand-Pass & Seymour http://www.legrand.us/product-detail/PassAndSeymour/IEC-309-Products/Fusible-NonFusibleMechanicalInterlock/Non-Fusible-Mechanical-Interlock/30-Amp/PS430MIR3W.pdf MECHA