This is a very unique low current regulated DC Power supply. The 20V DC, 500mA output is continuously variable & adjustable from 0-20V. The output voltage is adjusted with the help of control knob duly marked provided on the front panel. The output is electronically hort circuit protected. Operates on 110/120V AC, 60Hz and 220/240V AC, 50/60 Hz using voltage selector switch.Size 18 x 14 x 10 cm Weight : 1.3 kg