This hand controller is designed specifically for the new V2.5 power pack, as it now uses CAN bus to communicate with the ESC and battery pack. The older version used PWM and UART to communicate, so please make sure you check that you are using the new V2.5 power pack.
Throttle Hand Controller – SP140 V2.5
$220
Throttle controller for the SP140. Includes screen, controller board, case, strap and communication cable to ESC (USB-C version). For right hand pilots left hand throttle is typically preferred as it frees up the dominant hand to fix or act on any high priority tasks when flying.