Midwest Industries, AR15 BUIS, Low Profile, Flip-Up, Front Sight Gas Block, Fits Picatinny Rails, Black.
For use with a standard height, Mil-Spec Picatinny gas block. Folds to the rear and locks in the raised position. Uses standard A2 front sight post. Constructed of 6061 aluminum and hard coat anodized for a lifetime of service. Made in the USA.