The PU series have vortex impellers and large pump casings, for pumping sewage and waste containing fibrous material, submerged debris and large solids. Construction is in stainless steel and thermoplastic and they are fitted with high-performance motors. Available as manual or with a twin ball float switch, for automatic operation, it is adjustable and features an integral transformer to give a safe low voltage of 24 volts at the float end. The floats have a rounded shape to minimise false starting of the motor caused by water turbulence. An auto-coupling set is available as an optional extra (see here) to allow the fitting of guide rails on all models.