The specification: This seat post clamp with 34.9mm caliber is suitable for 30.8mm 31.6mm 31.8mm bicycle seatpost. High-quality materials: Our saddle clamp is made of high-quality alloys that are light, strong, durable and wear-resistant. Easy to Install: You only need to use the M4 hex wrench to complete the clamp ring saddle installation. Product features: This seat tube clamp makes it easier to adjust the height of the seat post and improves the safety of the seat post. Many applications: This saddle clamp is suitable for all types of bicycles, mountain bikes, folding bikes, racing bikes, etc. Product description Description: This seat clamp is a good partner for your bike - It is suitable for 30.8mm 31.6mm 31.8mm bicycle seat post. - Our seat post clamp uses high quality materials, exquisite workmanship, smooth, light weight, durable and wear-resistant. - This seat clamp is beautiful in appearance, we offer two different colors to meet your different needs. - Seat post clamp has a practical design and is easy to install. - Seat clamp not only makes it easier to adjust the height of the seat post, it also improves the safety of the seat post. Product information: Material: alloy Weight: about 22g Quantity: 2 pieces Size: - Caliber: 34.9mm (34.9 mm bracket for 30.8 / 31.6 / 31.8mm seat post) Package includes: - 2 x bicycle seat clamps