Removable seat cushion made of closed-cell, non-absorbent foam.
The Flexi hip cushion features two sewn-in pockets on the outside, which can be filled with the included foam inserts as needed for optimal seat adjustment. The hip cushions are secured to the seat using 20mm straps and buckles. The cushion is secured to the seat using four locking pins.
To do this, you need to drill four 7mm diameter holes in the seat; the necessary markings are located on each Lettmann seat shell.