Marine collar badge

[Pembird]

I recently acquired a royal marine collar which appears to be quite strange. It firstly is quite small compared to a normal badge, and, secondly the globe is held in position by a scalloped back plate which means it would always be on show rather than being hidden by whatever material it would have been attached to. Also the question arises as the the need of the scallop, did something sit above the badge. I look forward to your comments.