Pololu - Micro Maestro 6-Channel USB Servo Controller (Partial Kit)
4-channel rc servo controller - RobotDigg
USB 32Ch Servo Motor Controller Board, support PS2 WIFI with USB Cable - Robotools
Serial Bus Servo Controller: Hiwonder Serial Bus Servo Controller Comm
16ch Channel Way Servo Controller With Mini Usb Cable Control Board Usc-16 Driver Robot Arm Manipulator Humanoid Diy Rc Toy Car - Parts & Accs - AliExpress