I have tried a few different slings for my Rem 870 20 gauge and I’m happy to have found the Super Sling 2+ by Talon. The major advantages are the thumb loop which allows for one hand adjustment, the quick release and the quality nylon it’s made out of.
The sling adjusts easily to extend or shorten to your desired length. I have not had any slip ups from it either. The thumb loop fits comfortably when wearing the 870 and helps in adjusting as well.
The Talon swivels look and function excellent. You can quickly release the sling if you need to but they will not come unlatched unless you want them to.