Hi Rise Draughtsman Kit Complete (Footring, Gas lift and Glides)High Rise Draughtsman Kit Complete (Containing Foot ring, Gas lift and Glides The 5 star base not included) Our hi rise kit converts many of our standard height operator chairs for higher level working. We recommend using glides over castors with this for safety of the user Product Features: High rise kit to extend the height of an office chair Glides overcome instability of castors on higher chairs Adjustable foot ring Extended high rise gas lift 5