The Avonside Engine Company offered a range of standard narrow gauge tank locomotives that could be ordered with various gauge and cylinder diameter combinations. In order to ensure a long service life and low wear, some assemblies were made of harder steel than actually required and the friction surfaces on wear-intensive parts were made wider.

At the lowest end of the size scale, a four-coupled shunting locomotive was available, which was built in gauges between 1 foot 6 inches and 3 feet 6 inches. Cylinders were available in six, seven or eight inch diameters. Since there were otherwise no adjustments to customer requirements, larger quantities could be pre-produced and delivered directly on demand. No further information is available on the illustrated locomotive with the name “Imperial”.