BESGO automatic backwash valves made of PVC-U with hydraulic drive for water or air. DN 40 - 125 with adhesive nipple (can be glued outside), inner parts in stainless steel (V4A 1.4571), gasket Viton / PTFE - ozone-resistant, incl. solenoid valve with emergency manual override. Backwash valve incl. 3/2 230 volt solenoid valve, pressure loss: 20 m3/h = 3 mWC pressure loss.