The Córas Iompair Éireann 001 Class locomotive was manufactured by Metropolitan-Vickers at their Dukinfield Works in Manchester.

Initially they were fitted with eight-cylinder two-stroke, port-controlled Crossley engines.

These were a loop scavenge type, which utilised a patented principle that recycled the normally wasted exhaust-pressure pulse to boost charge air in the cylinder.

The original sandboxes, which were used to improve traction with the rail, were removed after a few years.

Four A class locomotives survived into preservation, the details of which are outlined in the table below: (Low bands) (High bands) The A Class is available as a 4mm scale (OO) ready-to-run (RTR) model from Irish Railway Models.