RC controller hook to add an offest to your original controller necklace holder. Some controllers are converted from FM to 2.4Ghz without repalce the position of the hooks, make the controller unbalanced. This pice can solve this problem on controller with horizontal hook, maybe you had to change parameters or trim to fit on yours. The spacer is made to use smaller screw than the original hook hole diameter. Tested on my Multiplex Cockpit sx.