Specifications: Made of aluminum alloy material, it has high hardness and strong wear resistance. It has anode surface treatment process and equipped with quick release lock design. The hollow design make it lightweight and easy to carry. There are three specifications for you to choose from, the 28.6mm seat tube clamp is suitable for 25.4mm seat tube, most of which are used for road bike or fixed gear bike, while the 31.8mm seatpost clamp is suitable for 27.2mm, 28.6mm seat tube, and the 34.9mm seat tube clamp is suitable for seat tubes such as 30.4/30.8/30.9/31.6mm. This quick-release locking seatpost clamp is a durable and lightweight tool, adding some beautiful colors to your riding and making it easy to adjust the height of the seat post. Item Name: Seatpost Clamp Material: Aluminum Alloy Features: High Hardness, Wear-Resistant, Hollow Design, Lightweight, Easy to Carry Inner diameter: 28.6mm/1.13", 31.8mm/1.25", 34.9mm/1.37" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Seatpost Clamp Dear customers, thank you for your support of the brand! Please note: brand products are only sold in this store. If you purchase branded products from other stores, will not be held responsible for any problems (including but not limited to quality problems, after-sales service, etc.). In order to protect your rights, please make sure to purchase from stores to avoid not being able to enjoy genuine product guarantees and brand services due to choosing other unofficial channels. Thank you for your understanding and support! Made of aluminum alloy material, it has high hardness and strong wear resistance. It has anode surface treatment process and equipped with quick release lock design. The hollow design make it lightweight and easy to carry. There are three specifications for you to choose from, the 28.6mm seat tube clamp is suitable for 25.4mm seat tube, most of which are used for road bike or fixed gear bike, while the 31.8mm seatpost clamp is suitable for 27.2mm, 28.6mm seat tube, and the 34.9mm seat tube clamp is suitable for seat tubes such as 30.4/30.8/30.9/31.6mm.