An early attempt to bridge the gap between motorcycle and conventional car, the nucleus of the Avon Trimobile was their own single-cylinder water-cooled engine, graduating from 4hp through 41/2hp and 5hp to an eventual 6hp RAC rating 98 x 114mm). This was rear-mounted, with a 3-speed gearbox, on strong Bridge Girders within a motorcycle-type tubular frame, although wheel steering was employed for the single front wheel. Chain final drive was used. In the absence of road springs the commodious 2-person seat was mounted on large coil springs, a refinement absent from the light delivery van version. The price increased from 80 guineas (£84) to 95 guineas (£99.75) in 1905, and a front-engined, 4-wheeler was then also offered at 106 guineas (£111.30), with conventional leaf suspension. London agents were appointed (Otto-Bennett Motor Co., Snow Hill), but sales remained mainly local and gradually petered out completely.