A patented design that is by far the most efficient suspension upgrade for hardtails. Saddle clamp to frame insert point (seatpost stack) needs a minimum 145mm. Parallel link design, responds to all bumps with none of the stiction common to all telescoping seat posts. 4" of travel back and down, means there is no pedal activated bob, or compromise on saddle height. At 495gm, the relatively low weight is only 200g more than a regular seatpost. Twin elastomers can be changed to tune performance to weight/riding styles.