The Pro-Gear Series “QSS” quarter turn gearboxes are rugged, industrial products, manufactured with a stainless steel 316 housing. All models in this series feature aluminium bronze (AB2) quadrants, as well as teflon coated high performance bearings.

All other main components which are exposed to a corrosive environment, such as the inputshaft, the position indicator and the studnuts, are also made from stainless steel 316.


The QSS series is highly suitable for all applications in highly corrosive environments such as pharmaceutical plants, chemical plants, off-shore industries and marine services.
The QSS series are intended for the operation of ball, plug and butterfly valves as well as power and process dampers. The usage of high grade materials provides a though, reliable and highly corrosive resistant unit for the automation of valves in today’s highly demanding industries.
The handwheels which allow a smooth operation are available in a variety of sizes and are made of stainless steel 316 only. This QSS series is also applicable with several other applications such as padlocking devices, limitswitchboxes and memory stops.

Performance specifications