These modular monitor cage rails will fit all the most popular monitor systems and allow you to mount NATO-compatible accessories such as handles, clamps, and articulating arms. Interchangeable Anti Twist Locator Pin inserts allow you to use all the most popular monitors and quickly secure them with a single bolt! SmallHD, PortKeys, Atomos, Blackmagic, Feelworld, etc... Accessories can slide along the length of the rail, and when its time to pack up, disengage one of the spring-loaded pins at either end of the rail and slide your accessories off. Use these to quickly attach a monitor to your camera or to build out your custom Directors Monitor. 1/4”-20 mounting screws are included, as is a hex wrench for installing the rail.