The GAC502PRO is an aluminium centre column adapter that allows the centre column to be adjusted from a 90 degree horizontal to a vertical position – or vice versa. One end of the centre column has a 3/8-16 mount for use with most tripod heads, and the other end features a sandbag or ballast slot. An object can be hung at the end to enhance balance and stability. The built-in quick release plate of the GAC502PRO is designed with ARCA style mount that can be used with Arca style heads. Two anti-slip studs are on the bottom of the plate. Also, on the bottom of the plate are additional ¼-20 and 3/8-16 mounting points – allowing it to be mounted to a video quick release plate or a number of other options. Notch-less dial allows users to achieve in their desired resistance with ease. Ballast can be hung on the column without slipping. Designed with Arca QR plate. 1/4 - 3/8 thread holes at the bottom of the QR Plate. Scales are on the centre column.