The AD-B3 modular base is the largest base in our modular lineup. Standalone it is a fullsize ACOG mount. Alternatively it can accept several different risers to accomodate a variety of uses. It is precision machined from 6061 T6 aluminum and finished in hard coat T3 Mil-Spec anodize. It features the patent pending Auto Lock™ Lever system to accommodate both in spec and out of spec rail systems.