Its high strength rebound motion of the shock release you in harsh driving conditions. Our products are made by high- qualified materials with technology and the advanced computer numerical control processing. It is good and replacement for some Gokart Quad and ATV. Pressure can be adjusted by springs and air (nitrogen) The is strictly monitored by standard to make sure the excellent performance and the good condition in the long- term use. Product Name: Motorcycle Shock Absorber Color: Black Material: 6063 Aluminum Total Length: 370mm(14.57inch) Eye To Eye Center Length: 340(13.39inch) Eye Diameter: 12mm(0.47inch) Spring thickness: 7mm(0.28inch) Spring Width(approx): 63 mm (2.48inch?? Max loading: <;=200kg/ each pcs <;=450lb/ each pcs Package included: 2* Shock Absorber 1*Wrench 2* 10mm copper rings NOTE: If you want more eye diameter size copper rings please click those photos. Please check the size details and make sure it will fit your bike before pur