An integral part of my weapon - BlackHawk Universal Single Point Sling Adapter

Easy to set up? Yea, once you get the castle nut off your stock. My M4A3 had never had the nut removed since coming from the factory. Be sure you have the right tool. Put the lower in a freezer for a few hours then heat up the nut with a blow dryer. Only then will the nut come off and still it won't be easy. Be sure to remove the stock over a flat, clean surface where you will be able to find all the pins and springs that will pop out.
Pros: Heavy duty, will last as long as the rifle
Cons: You will have to remove the stock to install

This review was written in the old system and had content requirements that are different than reviews written today.