This is the one... - SB Tactical SBPDW Mil-Spec AR-15 Collapsible Stabilizing Pistol Brace

If you're serious about utility and quality, it is very hard to beat the PDW without spending at least twice as much. In addition to being super-easy to adjust and operate, it is easy to install. It ships with everything you need except the buffer spring and the buffer itself. It almost falls into place when installing which is a few short minutes of minor effort. In addition to being near-perfect in function, it looks better than anything else out there. I was a little reluctant to spend the extra money on my first one. Silly me. I've bought several now and never looked back. No need to doubt your decision when this was it!