The Halfcage Rail attaches to the Zacuto VCT Universal or a href="http://store.zacuto.com/vct-pro-baseplate/ " target="_blank">VCT Probaseplate. It creates a solid, universal cage structure around the side and top of your camera rig and is adjustable to work with all camera shapes and sizes. It creates great stability, giving your camera a sturdy side grip and the ability to add a top grip. An included 3" Z-Rail attaches along the side of Zacuto's VCT Universal or VCT Pro baseplate with two ¼” 20 screws. The Halfcage Rail then attaches via a ratcheting, quick-release clamp at any point along the 5” Z-Rail. At its most compact height, the Halfcage Rail has a clearance of 5.5”. Expand the cage via four Allen screws on the handle side and the maximum clearance grows to 9”. The handle side has two rows of ¼" 20 tapped screw holes and a quick-release 15mm rod port to attach accessories. The handle itself is hand tooled, fine, three-quarter maple. The top portion of the Halfcage is a double-sided Z-Rail to attach a top handle or Z-Rail accessory. There are four threaded ¼" 20 screw holes for threaded accessories. The Z-rail is double-sided so accessories can be mounted on top or under slung. If you want to use the Half Cage Rail with the ColdShoe lock, please email sales@zacuto.com to make sure your model is compatible. Zamerican Articulating Arm Recoil Handle Axis EVF Mount Z-Rail Accessories Zacuto Z-Rail accessories are compatible with NATO, SWAT, RED, PICATINNY, and WOODEN CAMERA type rails. Zacuto products are proudly made in the USA and non-electronic products have a lifetime warranty.