Feature:Easy to install. Made of aluminum alloy, durable materials for long time service.Suitable for most of mountain bikes, road bikes, MTB, etc.There is a safe line mark on the seat post. Please insert at least above the minimum safety line.Specification:Material: Aluminum AlloyColor: BlackThickness: 2.5mm / 0.1" Dimension: 550x31.8mm / 21.65"x1.25"(L*D)Hole 1 Size: 31.8x27mm / 1.25"x1.06"(OD*ID)Hole 2 Size: 22x16mm / 0.87"x0.63"(OD*ID)Installation Step:1. Release the bolt of the old seat and unload the seat;2. Fix the seat on the new seat;3. Install it on your bicycle rack.Note:The size is measured by hand, so it may have a little 1-2 mm difference.Please do measure the actual outer diameter then choose the actually required diameter or measure the inner diameter of the frame tube before purchasing.
