Garelick Millennium Series - Seat Slide System - Smooth Series Adds 12 1.25cm to Pedestal height. Features Low profile design allows 360 of rotation and 6 of smooth, wobble-free fore and aft travel Heavy duty anodized aluminum slide plate has standard 5x12 hole pattern to accommodate standard seat mounting holes Positive Lock Spider - rotates 360, internal cup engages in 10 increments for positive stop lock Secondary twist control offers variable drag adj. and can be tightened to lock in place I