In the mid 1920's Wallis & Steevens Ltd., of Basingstoke, Hampshire felt there was a need for an easily maintaned roller for use on dirt roads - mainly in the Far East. Our 3 in. and 4 1/2 in. single cylinder engines are based on their Simplicity Roller, to the modeller these engines are just that simplicity, as far as the building is concerned.

The hauling power of these rollers, size for size does not compare with a traction engine, basically they are a lower powered, low geared unit designed for economical rolling, having a fore carriage which may be locked in the horizontal or allowed to swivel.

The construction of these engines in straight forward with few of the traditional complexities associated with large scale models of this type, having no orthodox firebox, only one set of driving gears, and an attractive sloping boiler design.

The Front and Rear rolls are cast in one piece, the inside is hollow and the holes are neatly and cleanly cast in both sides. The only machining necessary is to bore and face the hub and turn the O.D edges of the roll.