The Kimura is designed to work with most MMCX and 2-pin IEMs, however any non-standard shaped input jack may not be compatible. This is most likely to occur with recessed 2-pin jacks. The 2-pin version is 0.78mm, but should work with near-sized similar variants. We do not recommend swapping between different size 2-pin jacks frequently, as it add additional stress on the jack.
We have a 30 day return policy if you encounter any unexpected incompatibilities. Please let us know what works and does not so we can begin compiling a list of known issues.