S size. Sure you would like some force, but this is because of the fact that the short change buckle is held in place by friction. This may be the weak point to another person but I have found this to be of no challenges for me, the sling has https://magpul-pmag-d-60-ar-m430741.total-blog.com/srenmlight-tlr-6-and-tlr-i-hl-no-further-a-mystery-59933048