Designed to be safe and reliable source of low voltage D.C., for use in class rooms. Allows teachers to conduct experiments requiring a variety of direct current voltages while avoiding the decreased characteristics of partially exhausted dry cell. Comprising heavy duty transformer wound with copper wire with high lamination to avoid losses, selector switch and bridge rectifiers (consists of full wave silicon diode bridge rectifier) with jewel light and safety fuse. Output 2-12 V D.C.in steps of 2, 4, 6, 8, 10 & 12V.