This is the CC BEC 10A Receiver Battery Eliminator by Castle Creations.
$24.99
Eliminates the need for a receiver and servo battery pack
Draws higher voltage from the motor batteries and drops it to a
voltage level suitable for the receiver and servos
Requires Installation in the aircraft
Length: 1.2" (30mm)
Width: .6" (15mm)
Height: .4" (10mm)
Weight: .4oz (11g)
Input voltage: 5V to 25.2V (2S to 6S LiPo)
Current output: 12 volts input = 7 amps* continuous, 10 amp peak;
24 volts input = 5 amps* continuous, 7 amp peak
*Ratings are determined with a 5mph airflow on the BEC
Selectable Output: 4.8 - 9.0V via the Castle Link (sold separately)
Default voltage is 5.1V