A support device for supporting a rod or pole which is spaced above a surface, such as the ground. The support device includes an upright or vertical device, such as a post, with a shelf support selectively positioned thereto. The shelf support is adapted to support a barrier pole. The upright device...http://www.google.com.au/patents/US4989821?utm_source=gb-gplus-sharePatent US4989821 - Support devices for producing variable height barriers
