Gitzo Systematic Rapid Column for Series 2/3/4 Adding a Systematic column on a Gitzo Systematic tripod is useful when you require additional height as well as quick adjustment of the working height. This carbon fibre rapid centre column is compatible with Series 3 & carbon Series 4 Systematic tripods. The ''rapid'' column slides freely & quickly in the tripod shoulder & is locked & unlocked via a simple twist mechanism, offering the same strength & solid locking under heavy loads. The safety catch feature, when used together with recent Systematic tripods with a safety button, prevents the column from dropping out of the tripod even if it is inadvertently left unlocked.