A distinct fluting (middle of the seat is deepened) releases the driver's tailbone and disperses the driver's weight all over his bottom. Also, the seat gets broadened for ca.15 mm.
The padding consists of two layers, the upper one comfortably soft and the lower one avoids denting.
Special contours for the pillion's seat avoid the slipping when the driver has to brake.
Available in three heights (please note in the comment with number):
1: like the original one
2: lower (- ca. 25mm)
3: higher (+ ca. 25mm)

Your seat gets altered - you have to send it in!
The change takes about 2 weeks.