Carbon Fiber compares to Aluminum Alloy: Lighter in weight. Much more beautiful in appearance. Brighter in Color. Stronger in pressure resistance. Anti-Shock. Has proper elasticity, improving your bicycle’s class in minutes. Brand RXL SL Material Carbon fiber Appearance 3K Glossy/Matte, UD Matte Weight Brand Diameter 27.2/30.8/31.6mm Length 350/400mm Offset 25mm Usage Road/MTB Features Ergonomic Design: The whole series of products are ergonomically designed with 2 bolt clamps, which can provide a safe non-slip saddle position and compatible with more saddles. Adjustable saddle angle, easy to install and remove;Full Carbon Fiber: 100% full carbon fiber, ultra-light, durable, comfortable, tough, and high-strength alloy accessories provide safety protection for riders.Light-weight: Only about 210+/-10gAdjustable saddle angleOffset 25mm Precautions 1, Our seat tube diameter will be a little less than the size of the label. 2, Seat post diameter is 26.8 ~ 27.2mm Used in frame seat post 27.2mm. 3, Seat post diameter is 30.6 ~ 30.8mm used in frame seat post 30.8mm. 4, Seat post diameter is 31.4 ~ 31.6mm Used in frame seat post 31.6mm. 5, Some frame Seat post diameter is not standard, which means that the seat post can not be installed, please check that the seat post has to be properly secured with the saddle clamp. Assembly Instructions 1. Please check whether your bike parts are complete. 2.When assembling, please ensure that the diameter of the seat post column is the same as that of the frame seat post, and the size of the seat bow is the same as the seat post column. 3. Choose a suitable length, and when installing it on the frame, please insert it above the safety wire. 4. The port of the seat post can be cut in a regular bicycle shop. Customer Shows Install the product correctly, please follow the specified tightening torque (4Nm). Since it is made of carbon, we recommend tightening the body to support with your hands. Cracks can occur when strong tensions occur. Any quality problems please send me photos, we will try our best to help you.