We are the general agent of DNM in Chinese Mainland. All products on sale are original and genuine.Get some cushion for when it get bumpy. The DNM SP01 suspension seatpost is the perfect way to get some extra comfort on your ride.Technical Information:Material: aluminiumSystem: parallelogram, 1 coil springLength: 350 mm Travel: 20 mmDiameters: 27.2 mm/30.9mm/31.6mmSystem: Brass bushing parallelogram systemCompatible: 7mm saddle rails onlyWeight: 577/559/658g (27.2/30.9/31.6mm)Care Instructions:Every 6 months or 500 km the following steps should be taken:1. remove the seatpost from your bicycle2. loosen the adjustment screw and remove the coil spring3. clean the seatpost inside and out