Features:
-Main Body and Rails CNC Machined From 7075 T6 Aluminum Stock(60% Stronger Than 6061)
-Mil Spec 8625 Black Hard Anodized
-Mil-Spec Picatinny Dimensions
-Free Floating
-Blackened 416 SS Screw Posts for Rails and Clamping Bolt
-10-24 Grade 8 Screws
-Rails Precisely Located With Bugle Type Flat Head Screw In Combination With Screw Post
-Extended Clamping Screw Post For Increased Thread Engagement/Strength
-Does Not Interferr With Gun Stripping
-Virtually Full Length Barrel Nut Contact For Solid Lockup
-Easy Installation
-Made In USA

Installation Instructions For Long Forend (R4):

Make sure magazine is removed and chamber is empty.

Installation assumes bipod forend is installed and must be removed.

STEP1
Unfold bipod as if in use and removed spring that is between the two bipod legs. The spring legs sit in pockets and can be pulled out.

STEP2
Next the pin that retains the bipod leg on the pivot pin must be removed. With bipod positioned almost perpendicular with barrel as if in use but slightly folded back toward reciever pinch the bipod legs towards one another at the point towards the muzzle. This should have the pin positioned so that by using a utility knife or other thin narrow tool it can be pushed out. A toothpick or pc of wire may be needed to push it the rest of the way out.

STEP3
With the pin removed grab a hold of the bipod leg and pop him off the pivot pin.

STEP4
With bipod leg removed pivot pin is slid out of the gas block.

STEP5
Now remove the retaining clip that is located on the barrel nut.

STEP6
Now the the ring that locks the bipod in the folded position when not in use must be removed. This must be split. While the aluminum forend will fit if not removed, the interface strength will be greatly diminished if not allowed to go all the way over the barrel nut and against the shoulder. The split ring seems to work fine when reassembled in stock bipod configuration but I would not plan on being able to go back to that configuration to be on the safe side. To give yourself the best chance of going back to that configuration I would split the ring 180 degrees from the gas block orientation feature of the ring. I would also split it as thin as possible (dremel blade or hacksaw). We used snips. Slide off barrel nut and over the barrel to give clearance for cutting. Once cut slide gas tube back to remove ring.

STEP7
Next remove spring that sat behind the ring.

STEP8
With bipod assembly removed the aluminum forend can be installed.

STEP9
Remove clamping screw post and screw from forend. Slide forend over barrel and back onto barrel nut.

STEP10
Make sure forend is all the way back over barrel nut and against the shoulder.

STEP11
With gas tube in place orient forend so gas tube to forend top slot reveals are even.  Place clamping screw post in place and then screw.  Tighten down very tight your only limitation is the hex head. Blue Loctite is a good idea as well.

Installation Instructions For Short Forend (R3):

Same as above with following exceptions:

Before step 9  remove bridge from aluminum forend. It is secured by the last rail screw for the two side rails on the muzzle side.

After step 10 place bridge back into position by sliding it in the front. Top of bridge is toward the gas tube. Then place the two screws that you removed back into bridge when its lined up and tighten.