These rotary vane pumps are an excellent pressure/vacuum source for gas analyzers, medical devices, process samplers and other analytical instrument applications. They are also useful for material handling and many general automation applications. The pumps are quiet, reliable and mount in any position. The units operate oil free. The pump vanes have a service life of 1000 hours and are easily field replaced without special tools. Model 155 is provided with a 6 conductor wire connection. The motor(flow) can be reversed and there is a tachometric signal output each motor revolution. Performance can be varied by changing the motor supply voltage.