Battery Eliminator Circuit (BEC)
BEC stands for Battery Eliminator Circuit. It is an electronic circuitry commonly found in electronic speed controllers (ESCs) used in RC vehicles, particularly in RC cars, trucks, airplanes, and helicopters.

The BEC is designed to provide a regulated voltage output from the main battery pack to power the receiver and servos in the RC vehicle. This eliminates the need for a separate receiver battery pack, hence the term "Battery Eliminator Circuit." The BEC ensures consistent and reliable power delivery to the receiver and servos, allowing for smooth and precise control of the RC vehicle without the added weight and complexity of an additional battery pack.

Universal Battery Eliminator Circuit
A UBECis purely a device that converts high-voltage (ex. 25V from a 6S LiPo) to lower voltages to allow the full RC vehicles to be powered from one primary battery source.

 -- HOBBYWING University 

Accessories that make the difference. 

Compare UBEC models

ESC	3A (2-6S)	8A	10A (2-6S)	25A HV
p/n	86010010	86010030	30603000	30606000
Output Voltage	5V@3A or 6V@3A	5V or 6V	6.0V/7.4V/8.4V	5.2V/6.0V/7.4V/8.4V
Cont. output (A)	3A	8A/15A	10A/15A	25A/50A
Size	43mm*17mm*7mm	42mm*39mm*9mm	45*20*16.2mm	55mm*40.2mm*17.6mm
Weight**	11g	36g	34g	74g
	$8.40 Available to Ship soon Available for pickup Check authorized dealer	$18.49 Available to Ship within 24 hours Available for pickup Check authorized dealer	$24.99 Available to Ship  within 24 hours Available for pickup Check authorized dealer	$69.99 Available to Ship within 24 hours Available for pickup Check authorized dealer
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