100% new 500-3000W voltage transformer 110v to 220v voltage converter copper ... core is made of copper wire and this toroidal transformer can achieve high electrical efficiency of 95%. 4) ... hundred percent 500W,1000W, 2000W ,3000W voltage toroidal transformer for selling, welcome to choose. apply to power amplifier ... bristle brushes, polishing buff etc. 110v to 220v transformer 500w for pure sine wave