The diameter of the piston can be very small,normally between 3-200 mm Product DescriptionFlow: 0-6050 lphPressure: 0-500 BarPower: 5.5KW, 7.5KW, 380V / 400V, 50/60HzDrive System: single and two phase motor,Anti-explosion motor,Frequency conversion motorFlow Control: Manual operationProtection degree: IP55MaterialPump head: SUS304, SUS316,SUS304+PTFE,SUS316+PTFEDiaphragm: PTFEValve: SUS304, ...