Prologo zero ii tirox road saddlean ideal saddle for short or medium distance riding where a frequent change in position is necessary. New tirox rails stainless steel for a lower weight than the old ti 1.4 rails, greater resistance and vibration absorbtion.shape flatend use roadlearn more, with the prologo buying guide.featurestirox rail rail light alloy steel, this material is highly resistant to traction, and torsion for its light weight it's for these reasons it is used in used in the aviation and aerospace industry. Tirox then turns out to be a rail with a good balance between weight and strength, that doesn't fear the normal stress that addresses a bicycle.connect power control prologo's patented name for these new saddles featuring dense bunches of short, suction cup like gel polymer tubes. This technology has been used in moto gp and formula 1, largely in gloves for the racers, but prologo are the only ones to use it in cycling.size mm 278 x 134weight gr 210base carbon fibre injectionrail tiroxcover microfiberpadding light pubuy prologo components from chain reaction cycles, the world's largest online bike store.