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This is a replacement charging handle for the GHK G5 GBBR. This model is a Small HK style with a skeletonized center.
For a other versions, check out the H&K style handles, which offer a more traditional form and are available in both small and large sizes.
It should swap straight across with minimal if any fitment or sanding, though occasionally a print will have slightly tighter dimensions and will need a little finishing work. Most common are the pin holes, which are difficult for the machines to make nice round shapes that small.