Hammond 185F20 Power Transformer 115/230VAC Input 10V/20V Output (Box of 6 units) Go to amazon.com Related posts Expert choice for 20 volt transformer Feature115V or 230V ac Transformer10V 13A and 20V 6.5A OutputCE UL Description115V or 230V ac Transformer. 10V 13A and 20V 6.5A Output. Bulk packaging is 6 pieces per box.