American Defense Mfg. ARCA to Picatinny Mount, Fits Tripod Heads with ARCA Swiss, Anodized Finish, Black AD-ARCA-TP-TAC The AD-ARCA-TP ARCA To Picatinny Tripod Adapter enables you to attach an ARCA style Tripod to your railed forearm. It is precision machined from 6061 T6 aluminum and finished in hard coat T3 Mil-Spec anodize. It features the Patented QD Auto Lock(tm) Lever system to accommodate both in-spec and out-of-spec rail systems.