KST X15-1208 Mini Size Digital Servo is a great choice for helicopters ranging from 430mm-570mm rotor blade size requiring mini servos such as the Align T-Rex 500, Mikado Logo 480, MSH Protos 500, and SAB Goblin 570. Additionally these servos can be used in other RC applications where the physical dimensions, and torque/speed ratings suit the need of the RC application.