Over all, this is a really good servo with great specs and well design. KST also said that unlike any other servo, the X20 generates no counter EMF in any working condition as it has the all-new design servo circuit board, so your flybarless system and receiver will not be interfered or have any weird behavior any more.

Just give them a try, and you will love them.

KST X20-1035
Operating Voltage:Dï¼£6.0V-8.4V
Size:40.50*20*38mm

Torque:
12.00Kg.cm@8.4V   
10.30Kg.cm@7.4V  
8.50Kg.cm@6.0V 

Speed:
0.03sec/60°@8.4V    
0.035sec/60°@7.4V   
0.04sec/60°@6.0V   

Weight: 72g
Working Frequence: 760us/560Hz
Motor: Brushless    
Ball Bearing: 2BB