Have a QD point? Want to hook on your MS2/3 or other non-QD sling? Magpul Industries Corp. has a gadget for that.
Can look a little funky (as demonstrated here on the Fortis Manufacturing REV rail) but it’s small and locks in totally solid; no rotation once tightened in to place.
I picked up a pair of these as so many forends incorporate QD points right in to the metal and having these on hand means you can almost instantly switch from needing a QD sling to being able to use any sort of hook you like.