The Manfrotto 055XPROB Aluminum Tripod Legs builds on the success of the 3011/3021 series. It features the Manfrotto-patented horizontal center column feature, which allows the center column to flip quickly and easily from vertical to horizontal. By extending the column to its highest vertical position, it can be swung over to horizontal without removing the head or disassembling the column itself. The ergonomics of the leg-angle release mechanism and the quick action leg locks have also been improved.