About this item Pressure can be adjusted by springs or air (nitrogen); Operation of the coil-over springs and air cylinder is helpful to reduce the shock. Universal fit for most 375mm Motorcycle Shock Absorber for Dirt bikes, Gokart, ATV, all Motorcycles and Quad. A Pair of Round Hole 340mm Aluminum and Solid Steel Shock Absorber Shock Absorber bottom/ends type: Round End No instruction included, professional installation recommended. See more product details Color:blue&silver Specification: Color:Full black/blue+silver Dimension:Total Length: 400mm (15.75″) Length of Eye to Eye Core: 375mm (14.75″) Eye Diameter(with bushing): 12mm  Eye Diameter(with bushing removed): 16mm Eye Thickness: 21mm Eye Maximum Tensile Strength: 2,000 Kgf Spring Thickness: 8mm Spring Width: 60mm Working Stroke: 68mm Spring Stiffness: 110 kg Maximum load: 300 kg (660 lbs) Air Reservoir: Adjustable Factory Air Pressure: 0.4 Mpa