The Moeller part number PKZM1-4 is distributed by Electrol. The product that you are looking to replace may be brand labeled Klockner-Moeller, Moeller, Copperlogic or Eaton. Moeller, based in Bonn Germany, is now a wholly owed division of Eaton Corporation. Moeller products include a broad range of IEC motor control, low voltage devices and systems including breakers (molded case and din mount), contactors, MCC's, pilot devices and PLC's. Moeller products are used extensively in Mining, Pulp & Paper, Food Processing, Nuclear Power and Marine applications. Electrol has one of the world's largest inventories of legacy Moeller NZM series breakers and accessories including NZM4, NZMH4, NZMS4, NZM6, NZMH6, NZM9, NZMH9, NZM10, NZM11, NZMH11 and NZM12.