Ideal for areas that can be made temporarily available for traffic but at certain times need to be cordoned off eg parking bays pedestrian areas car parks etc once unlocked the built in damper enables it to rise out of the ground socket automatically to lower simply push the top of the post until it is fully retracted manufactured from steel fitted with a lock operated by a triangular key overall surface height x diameter 900 x 76mm installation is by means of an integral ground soc