Warne M-LOK ARCA rails are made from 6061 T6 aluminum and act as a versatile mounting point for your rifle. Whether you seek the ability to attach your rifle to a tripod, the freedom to move your bipod to your desired position, or use one of the many ARCA style accessories available, the Warne M-LOK ARCA rail can handle it all. 4-inch size M-LOK is a registered trademark of Magpul Industries Corp.