The Metrel A1424 Welding Equipment PAT Adaptor can work with the Metrel OmegaPAT or SigmaPAT and the Metrel A1422 Three-Phase PAT Adaptor to perform a range of tests including leakage current measurement, earth bond continuity, insulation resistance and no-load voltage on ARC welding equipment. It has a ø21mm CX22 connection.