Hard-anodized, machined, aluminum riser clamps to flat top receivers so you can mount your scope using standard-height rings at eye level. Hollow center doesn’t block your vision of iron sights. Attaches to Picatinny rails and receivers; lets you use Picatinny and Weaver-style rings. SPECS: Hard-anodized aluminum, black, matte finish. 5-3/8" (13.7cm) long, 39/64" (16mm) high. Made in the U.S.A.