Building a functional and efficient dry suction system with a variety of working functions requires some kind of valve to open or shut the air stream.
The line of CP valves consists of various models - mechanical, electrical or with electrical switch built in for activation of the suction motor.
The hand valves come with or without an electrical switch for activat- ing the suction motor.
Furthermore they are available for inserting between a flexible mouth piece and a noise reducer on Superflex suction arm. 
 
Features of the valves include:
 
Manual or motor regulation
With or without a switch system
Better ergonomic
Very tight closing 
 
Download technical specifications here.