... electromagnetic metering pump is handled by the micro-controller, with a variable stroke length and frequency, solenoid-driven diaphragm metering pump ... .82AC220V/50HZMaterial Table Diaphragm: PTFE Pump head: PVC, PP, PVDF One-way valve: PVC, PP Bottom valve filter: PVC, PP Injection ... , PP Hose: PVC, PE, PTFE Sealing: PTFE Frank metering pump for waste water treatment made in China