Name: Mountain bike quick release pneumatic shock absorber front fork Size: 27.5/29er Stroke: 110mm Opening: 100 mm Brake: Disc brake Axle: 9mm quick release Color: color, black Version: Shoulder control (straight tube) Stand pipe length: 220mm Stand pipe diameter: 28.6mm-30mm Upper fork pipe diameter: 32mm Lower fork tube diameter: 38mm Material: aluminum alloy Weight: 1960g (27.5er) The function of the air pressure valve: the soft and hard strength of the shock absorber can be achieved by adjusting the air pressure. The lower the air pressure, the softer the front fork, which is suitable for bumpy roads; the higher the air pressure, the harder the front fork. Suitable for riding on flat roads Reminder: To adjust the air pressure, you need to use a special cylinder for the front fork. If you do not have a professional air cylinder, please do not vent the air at will.