The Strike M-LOK ARCA Rail Adapter enables easy mounting on ARCA Swiss mounts. Angled front corners to reduce snagging during ARCA mount insertion. Securely and conveniently adapter M-LOK to ARCA Swiss. Threaded holes along adapter rail for SI ARCA accessories. Machined from 6061-T6 aluminum, ARCA Swiss mounts have become the industry standard. With the Strike M-LOK ARCA Rail Adapter, you get a low-profile lightweight option to adapt most M-LOK surfaces.