Bi-pod adapter - Harris Engineering Number Studs Fits Colt Ar-1 5

I would have given this a 5 star rating but the installation instructions were lacking in detail. I had to call Harris Engineering to have them explain how to install the adapter. Their explanation took 2 minutes and the part was installed, along with the Bi-pod. Once installed, it was very clear how the adapter worked and the bi-pod fit solid and firm on the rifle. I told them that their written instructions needed to be as clear as their verbal instructions. I would consider purchasing this item again, to install on a second rifle, so I can switch the bi-pod when needed.