Not sure what barrel length you have, but I use a MagPul MS3 on a 12" FN barrel and it works great. It can be either configured as a single point, or conventional sling. Works great on mine either way. Single point hooks to a Magpul ASAP sling attachment point. It can be unclipped at the "Y" and hooked to the sling attachment under an A2 sight or a rail mounted sling mount and used as a conventional sling. Mounting clips can also be locked. Not inexpensive, but well made and versatile. Going to buy a couple more of them.
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