This lightweight and comfortable vibration damping post allows you to fine tune your saddle position with a single bolt adjustable head and two setback optionsfact 3k sl high strength carbon construction blends high durability stiffness and comfortincludes hardware for 7x7mm and 7x9mm railsnew design cylindrical aluminium head assembly adjusts fore aft and tilt with an easy access single boltintegrated vibration damping zertz viscoelastic polymer insertsetback 21mm setback 0mm setbackdiamete