Very useful tool - Real Avid Lug-Lok Upper Vise Block

I was a bit hesitant on buying this tool because of the price but I'm glad I did. I can't imagine trying to install a barrel without this tool. The lug-lok is a well made piece of cnc aluminum that fits perfectly inside the upper and barrel. Once clamped into the vise it makes working on the upper receiver a breeze especially when torquing down the barrel.