Is this compatable for a jbl xhd?
Probably not? There is a recess with rails in the handle. I actually also had that problem,but made a piece out of aluminum which works. I also use the same reel on other guns. I taped them directly and used a sealer. It dose not detach quickly,but it dose work.
Hope this helps. Also,a Omer trigger could be made to fit the shaft. And that would have the mounting you need.
The bracket is designed for an Omer speargun. Therefore, it is compatible to an Omer. A JBL is is a totally different gun. Compatibility is almost always an issue when using parts designed from one gun manufacturer to another. Since I do not own, nor care to own a JBL, I can't tell you whether or not the bracket is compatible. You are better off asking the members on Spearboard website or Scubaboard website. The guys in Florida use JBL's more than any other place. Good luck