Within Fizik’s Spine Concept system this saddle is categorised as a " Chameleon" type. This means its designed for those who have medium spine flexibility & who’s pelvises have a low amount of rotation when pedalling. Advanced Construction The shell is manufactured using a nylon that’s reinforced with carbon fibre. This keeps the weight low & allows just enough flex to allow your pelvis to obtain its natural movement range, maximising pedalling efficiency. Finishing off the Antares R3 Open is high-quality Comfort Core foam & a super-durable Microtex cover.