These two kits can be used separately; or assembled together to create a dual rail power supply. Current up to 1.5 ampere output. Both kits feature; reverse polarity protection; LED power "on" indicator; IC regulator; variable output voltage; low noise; AC or DC input and up to 37 volts output. Complete details for selecting a transformer (transformer is not included; you must supply input voltage of 3 volts more than desired output) are included. A thorough description of assembly options is included with each kit.