PSU box Constant Current/Voltage 0-50v 5A

Custom PSU enclosure

you will need some basic electronics knowledge to wire this up.

Parts list
1X spst rocker switch http://www.jaycar.com.au/PRODUCTS/Electromechanical-Components/Switches/Toggle/SPST-IP56-Heavy-Duty-Toggle-Switch/p/ST0581

1X cover http://www.jaycar.com.au/Electromechanical-Components/Switches/Toggle/Missile-Switch-Protective-Cover/p/ST0578

1X binding post Red http://www.jaycar.com.au/Interconnect/Plugs%2C-Sockets-%26-Adaptors/Banana/Fully-Insulated-Gold-Plated-Bin