ProMag AR-15 Roller Follower 5.56mm 30 RDs FDE Polymer Features: These magazines were designed for professional shooters and law enforcement personnel whose lives depend on a perfect shot every time. Expertly machined for exceptional quality and guaranteed to feed and function for every shot. ProMag magazines include a lifetime guarantee if you ever have a problem with their magazines; simply return them to ProMag for replacement. When you need a cost effective aftermarket replacement mag that you know you can count on you need a ProMag! This magazine is made from Technapolymer with an anti tilt roller follower and anti fatigue chrome silicon spring for flawless operation. The anti tilt roller follower will provide reliable feeding and the anti fatigue spring will work even after being preloaded and stored for up to 6 years! ProMag AR-15 Roller Follower 5.56mm 30 RDs FDE Polymer Specifications: ProMag Rollermag AR-15 Magazine RM-30-FDE 5.56 NATO/.223 Remington 30 Rounds Smooth Feeding Anti Tilt Roller Follower Anti Fatigue Chrome Silicon Spring Technapolymer Magazine Body ProMag Lifetime Warranty Flat Dark Earth