No external power supply Since it is the non-operating Acetrap ball float drive, no power supply is required.No problem with oil in detecting condensate. Very good maintenance. It is a product which is verified by patent of USA and Germany. Simple and Robust Zero air loss enables quick payback on investment. As a small size of use, it can also be applied to the field pipe lines and others. Test Key is built in, so you can check the operation at any time. Durable The internal diameter of the seal discharge is 7∅, so the small size pipe scale or foreign material is easily discharged. Life of Diaphragm verified 1 million times based on cold tap water. Once installed, it can be used for as long as a compressor.