Been looking for a good non-metallic sling mount option that can be easily removed. I'm planning on using it on a short FCD handguard that doesn't have QD mounts, and not wanting to take up space/weight with adding a QD mount to the limited space.

The Q Sling Devils looks to be perfect but it doesn't seem like many people are using them. They're pricey for what they are. Is there some better technique for tying paracord or some better product or should I give them a try?

Or you can just tie the 550 cord directly to the gun without $20 worth of two tiny little pieces of plastic....

What's a good knot to detach and reattach the sling easily?

What reason for non-metallic?

If I needed to remove it but can't or don't want to use a QD swivel & cup I would go with this: https://www.blueforcegear.com/uloop

It's still lightweight, cheaper and probably a lot more durable than a sling devil.