Sure, here's a refined and simplified title focusing on the product keywords: Aluminum Alloy Bike Seat Post 17.7inch Replacement φ 25.4-31.6mm

Product Description and Installation Tips:

If you find it challenging to turn the fixing bolt initially, please insert the post into the bike frame hole and lock the seatpost clamp. This will allow you to easily turn the bolt with a hexagon screwdriver. Once the bolt has been moved the first time, it can be adjusted smoothly thereafter.

Specifications: - Material: 6061 T6 Aluminum alloy - Color: Black - Weight: Approximately 380g - Length: 450mm - Tube thickness: 2.5mm, high strength - Tube Outer Diameter: 25.4mm, 27.2mm, 28.6mm, 30.4mm, 30.9mm, 31.6mm

Extra Length: The extended length helps to raise the height of the saddle, allowing taller riders to avoid excessive forward bending.

Features: - The clamp is adjustable, enabling you to fine-tune the saddle tilt angle.

Package Includes: - 1 x Bike Seatpost

Important Note: It is generally not recommended to load more than 220 lbs (100 kg) on this seatpost.

Size Selection: The diameter number refers to the frame seatpost hole size, but the seatpost itself measures slightly smaller than the indicated diameter. For example, a 25.4mm seatpost may only measure approximately 25.0mm to 25.2mm.

How to Measure and Confirm the Diameter You Need: There are two ways to determine the exact diameter required for your bike:

1. Check the diameter marking on your old seatpost. If it's labeled "Φ25.4," then you should purchase a new 25.4mm seatpost.

2. If you have a vernier caliper, measure the diameter of your old seatpost or the inner diameter of the seatpost hole. Then, select a new seatpost with a similar measurement, such as 27.2mm if the measurement is around 27.1mm.

3. If you don't have a vernier caliper, you can use a small stick to measure the inner diameter of the seatpost hole (refer to the provided picture).

Important Note: The actual measured diameter of the seatpost will be slightly smaller than the number printed on it. For example, a 25.4mm seatpost may only measure approximately 25.0mm to 25.2mm.

Extra-Long Length: The seatpost measures 17.7" (45cm) in length, which helps raise the saddle height to accommodate taller riders, preventing them from having to bend excessively forward.

Compatibility: This replacement seatpost is suitable for most bikes, including mountain bikes, road bikes, and other universal bicycles.

Adjustable Clamp: The clamp design allows you to easily adjust the tilt angle of the saddle to achieve a comfortable and horizontal position.

product information: