Help with 30mm Link Identification

Hello everyone.

This is my first post. If I can impose on the wealth of knowledge out there, I need some help identifying some 30mm links that I have laying around. One photo has a MK 44 link for size comparison. It appears that someone has spray painted over a phosphate coating (partially chipped off in one photo). The only marking is “HSS” or “SSH” (if upside down).

If anyone can help, I would appreciate it.