HY3005-3 Linear Variable DC Power Supply, 2 Variable + 1 Fixed, 0-30 VOLTS @ 0-5 AMPS by Mastech voltage is variable from 0 to 30 volts Output Current: 0-5 AMPS Protection: Current limited & Short circuit protection Operating Temperature : 0 - 102 F ( 0 - 40 C), Relative Humidity: 90% Constant voltage / Constant Current