Can operate dry without damage. Free from vibrations, very quiet. Internal bypass that limits input pressure. Motor with permanent magnets and selflubricating shaft. Thermal protection on the motor that stops it in case of accidental overheating. Protection against polarity reversal. Internal stainless steel bearings.4 plug-in fittings (2 x 1/2" threads + 1 x 14-mm straight hose adaptor + 1 x 14-mm 90° hose adaptor) and plug-in inlet strainer,