This is a very simple board that takes a 6-12V input voltage and outputs a selectable 5V or 3.3V regulated voltage. All headers are 0.1" pitch for simple insertion into a breadboard. It can be either powered from 6-12 DC2.1 power jack or from USB power.  The maximum current it can provide is 500mA. 

• Input voltage: 6-12V (Power Jack) 5V (USB)
• Output voltage:3.3V/5V
• Output current:500mA
• On/Off switch
• Power status LED
• Pin Head 5/3.3V output
• Central positive DC2.1 power jack

• Schematics

• Breadboard Power Unit (Assembled) x1