hexTronik UBEC. Will supply a solid 5v or 6v to your reciever with a  2 to 5S Lipoly pack. Specifications; Output: 5v/3a & 6v/3a (Selectable via jumper) Ripply: <50mVp-p(@2A/12V) Input: 5.5v~23v (2 to 5s) Size:41.6mm*16.6mm*7.0mm Weight: 12.5g UBECs are used by connecting the input wires to the battery and the output to the receiver. This allows your Speed Controller to run cooler, and safer as you now have an external circuit to power your receiver. Should the Speed Controller be overloaded and fail, you still have control of your plane.