This tiny step down regulator can supply 3v, 5v, 12v, etc to your flight controller, receiver, camera, vtx, etc.  Although rated for 3A, it is not recommended to go above 1.6A without cooling.  Versatile items like this is a must in every fpv pilot's bag.

Specifications:

• Input voltage: 4.5-28V
• Output Voltage: 0.8-20V (adjustable)
• Output current: rated current 3A(MAX).
• Switching Frequency: 1MHz
• Output Ripple:less than 30mV
• Efficiency:96%(max)
• Operating temperature: Industrial grade (-40 C to +85 C)
• Module Properties: Non-isolated step-down module (buck)
• Size:22*17*4mm

Includes:
1x D-Sun 3A Step Down Switching Voltage Regulator