These are two custom-length standoff spacers designed to be used with other models available on my profile.

For use with the XT60 Holder only:
Use the 21.25mm spacer directly on the standoff, then slide the XT60 holder on top.

For use with the DJI O3 Camera Mount:
Start with an 8.75mm spacer, then add the camera mount. After that, add another set of 8.75mm spacers or the XT60 holder to keep everything firmly in place.