The drive pins are adjustable to control the engagement depth, to prevent scratching the barrel. Now you can take the brake off for cleaning, and index it perfectly every time! Plus you can control how deep the brake is set, to get the most accuracy from the big AR.
This tool also fits the AR-15 Castle Nut grooves, and works great for installing / removing buffer tubes.
Technical Information: CrossTac AR-15/AR-50 Spanner Wrench