There are no instructions for installation, either on Mesa's website or the internet that I can find. This kit is for both the A300 and the 1301, so it has parts for both. You will have an extra sling attach plate depending on which model you are putting it on. In my kit, there were 2 lock washers with a spot of rubber cement like you find in packaging sometimes holding them together. The serrations are different on either side of the washers, so there is definitely a right and wrong way to install them, but without instructions, I don't know where to put them. I just guessed and winged it. The plate on the inside that goes under the nut and holds the stock onto the shotgun is a slop fit. The hole is drilled way too big and just floats around on the stud. It works, but lazy loose tolerance hardware is a pet peeve of mine. I wanted a pistol grip to keep my thumb off my nose during recoil, but wasn't too excited about the short LOP. I figured I'd just stick a spacer between the butt and the pad. It's not possible with this as the pad snaps onto the rear of the stock. It's fixed and so there is no way to add a spacer if anyone is thinking along those lines.