The 408M Micro Double Valve Pump has a remarkably small and flexible design. It is a pneumatic pump which operates under the same principle as the standard DVP, but uses coaxial PFAS-free PTFE tubing with stainless steel valves and filter. Small enough to fit in 1/2" (13 mm) tubing and all channels of the Solinst CMT System, the Micro DVP is ideal for low flow sampling in narrow applications. A flow rate of 20 to 200 ml/min can be obtained to depths up to 73 m (240 ft).