Uses 11 slot rails (4.515" long)
Prices (Include Shipping):
R5 SU/PLR22 Forend
Complete with 3 full rails (11 slots)                    $140.00 (comes with rails assembled)
Body only (no rails)                                            $  80.00
(1) 11 slot picatinny rail with hardware              $  23.50

SU/PLR22 Aluminum Forend Info

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
-Weighs Approx. 8.5 ounces
-Made In USA
 
Installation Instructions:
Tools required:1/8" allen wrench and flathead screwdriver.

Remove magazine and make sure gun is unloaded by checking chamber.

Remove clamping screw post and button head screw from forend.

Slide forend over barrel and onto and over barrel nut all the way back.

Orient forend and place screw post in place and then place button head screw and tighten.