Made specifically for use with the 4 series tripods, the Benro AGC4N Geared Column enables you to mount a large variety of cameras and other accessories. It comes with a 3/8"-16 threaded stud on both ends, which give you the freedom to either change your camera's location instantly without removing the arm or mount two tripod heads simultaneously. The basic twist lock ensures that the column remains in place every time. The column’s geared movement is controlled by the main handle that moves the column vertically down or up in tiny increments. Lastly, this column is constructed from aluminum, which makes it sturdy.