Variacs / Dimmerstat is a regulating device also know as autotransformer. It is a single winding transformer which has a common primary and secondary winding. In this range we have Single | Single Phase Flush Back of Panel Open Type | Input 230V A.C. Output 270V A.C. 50-60Hz| Three Phase Flush Back of Panel Open Type | Input 415V A.C. Output 470V A.C. 50-60Hz | Single Phase Portable Table Floor Mounting Enclosed | Input 230V A.C., Output 270V A.C., 50-60Hz | Three Phase Portable Table Floor Mounting Enclosed | Input 415V A.C., Output 470V A.C., 50-60Hz | with Current range from 0.75 Amp to 50 Amp.