An impressive mid-20th century McNab Brothers bridge-mounted engine revolution indicator and control, manufactured in Bridgeport, Connecticut, U.S.A., and retailed by McNab Brothers Limited, Montreal. Constructed in heavy cast bronze and mounted on its original pedestal, the instrument features a large glazed dial with a 0–220 RPM scale, original pointer and rear control wheel marked “Increase” and “Decrease”.

Designed for use on a ship’s bridge, it enabled the helmsman or officer to control or indicate engine revolutions to the engine room, forming an essential part of a vessel’s propulsion system before modern electronic controls. With its superb industrial design, original patina and impressive size, this is a striking piece of authentic maritime history, ideal for collectors, museums, yacht clubs or nautical interiors.