A4-style flattop upper receiver is forged from extra-strong 7075 T6 aluminum, with a 5" long rail to accept your tactical accessories, including Weaver-style rings. Finished with mil-spec, hardcoat, black anodizing for protection from scratches, mars, and abrasion.
SPECS:
7075 T6 aluminum, hardcoat anodized, black, matte finish. .250" (6.3mm) diameter pivot pin holes.
Catalog page 3