1、It is made of aluminum alloy with high hardness and corrosion resistance. 2、The seat tube has a ruler to adjust the height, and the installation is more specific. 3、Each type of seat tube has a lower limit for installation, to ensure that the part below the safety line of installation is completely inserted into frame seat tube, to ensure riding safety! Note: Weight limit: 80KG/2821.9oz. 4、The tilt Angle of the cushion can be adjusted without pole, which is convenient and safe. 5、Suitable for most of road bikes, fixed gear bikes, mountain bikes, downhill bikes, track bikes. Item Type: Bicycle Seatpost Material: Aluminum Alloy Color: As Pictures Shown Product Diameter: Approx. 31.8mm/1.3inTotal Length: Approx. 60cm/23.6in Weight: Approx. 433g/15.3ozLoad Bearing Limit: 80KG/2821.9oz Quantity: 1 pc Installation details Then push the screw through the two holes and tighten the screws in the two lugs lay the saddle in reverse and put the seat piece in Then install the tube upside down as shown in the picture, remembering that the lower side is in the front and the higher side is in the back lock one side screw first and adjust the middle clamp and screw of the seat tube to adjust the Angle Finally lock the screw 1 x Bicycle Seatpost 4 x Accessory 2 x Screw