Lock, ARG 1200 class unit 1203, a Clyde Engineering EMD model G12C serial 65-427, one of fourteen originally built between 1960-65 for WAGR as their A class A 1513, fitted with dynamic brakes and financed by Western Mining Corporation, started working on the Eyre Peninsula in November 2004 with two ALCO units 850 and 905 drag their grain train over the grade past the location sign and down into Lock. 11th January 2006.