Large space - this bike tail bag has a large capacity and can store many small items, such as keys, headphones, mobile phones, wallets, glasses, gloves, small repair tools, energy bars, small pumps, power banks, mini flashlights, USB cables, batteries, pens, other accessories, etc., without the need for a backpack. Inside, there are small mesh and spring straps for small items such as gadgets that need a separate space.Hard shell surface - made of high-quality EVA material, saddle bag surface has texture, luster, durable, waterproof, shock-proof, not easy to deformation. You can really feel the difference between the material of the saddle bag and the general product. In addition, the smooth surface makes the bike seat bag easy to clean.Safety design - The rear of the bicycle storage bag is reserved for taillight mounting holes for hanging taillights (without taillights). Silver reflective signs on the back and reflective belts on both sides of the seat bag increase night visibility when riding at night, making you safer at night. The design will protect your night riding.Easy to install - Only two steps are required for successful installation, two mounting belts simplify the mounting system, one mounting belt on either side is used to secure the bike seat and can be adjusted, and the rear mounting belt is used to secure the bike tube. What's more, it won't touch your legs when you ride.