High Quality This bicycle saddle tube head is made of premium aluminum alloy material, sturdy, durable, and lightweight. Suitable For The bike seatpost head fits most single pin lockout seatposts on the market. Install Needs 1. The original seat tube is fixed by a single screw, the hole diameter is 8mm. 2. There is an anti-slip groove at the installation position. Proper Size The bike seatpost clamps head saddle pipe is 5.5cm x 3.3cm x 5.1cm / 2.17inch x 1.30inch x 2.01inch, easy to use. Product Use The bicycle saddle tube head is a good replacement for the damaged seatpost head, a great bicycle accessory. Specification: Material: Aluminum Alloy Color: Black Size Chart: 5.5cm x 3.3cm x 5.1cm / 2.17inch x 1.30inch x 2.01inch Package Includes: 1 x Bicycle Seatpost Head Saddle Pipe Head Note: Please allow slight errors due to manual measurement and different monitors.