Roberts GT 2000 Knee Kicker,Is a very reliable,professional and durable knee kicker,probably why every carpet fitter has this brand in his tool box,their top of the range knee kicker,has a die cast aluminium body for maximum strength with a smooth and positive adjustment dial ,extendable in 5 positions from 47-57cm,has a wider head for more gripping power,a large buffer pad allowing for added knee protection,napgrip inserts and adjustable base plate.A must have for any carpet fitter serious about laying carpet.