KE Arms is now offering the Easy Sling Adapter for the KP-15 lower receiver. The Easy Sling Adapter makes use of the rear sling mounting slot on the KP-15.
If you have used this slot before, you know that it can be a bit of a hassle to get the sling tight enough. The adapter is designed so that it is self-tightening as the sling is pulled. It is also much easier to swap slings from the adapter than the fixed slot.