VCMs are speed controllers for applications where VC accuracy is not required. The precise speed controllers are maintenance-free and ready to use. The threaded body makes installation and adjustment very simple. They can be precisely adjusted, have no free stroke, are temperature stable and move smoothly. The VC series up to the 55 mm stroke is hermetically sealed by a proven rolling diaphragm. The rolling diaphragm also serves as an oil reservoir and return spring. Thanks to the finely adjustable segment, speeds of up to 12 mm/min are also possible at low drive forces.