Features: Engineered with Ethylene Vinyls Acetate Copolymer materials, this bicycles seat bag delivers superior impacts resistance and durability, solving the vulnerability of traditional soft bags while securely storing tools for long distance cyclists. Featuring expandable design (up to 6L capacity) and a patented quickly release systems, it adapts to varied gear needs and installs in 10 second without tool. Ideal for commuters, and outdoor enthusiasts seeking reliability cycling storage that withstands terrains and sudden weather changes. Designed for rainy rides or multiple day trip, its waterproofed zippers and splash resistant surfaces keep essential dry, while the detachable structure doubles as a crossbody bag for city errands. Combining functionality with versatile utility, this bikes tail bag redefines cycling accessories by merging weatherproofed protecting, tool organization. Specifications: Dimension:190×103×92mm/7.48×3.62×4.05in Component:Ethylene Vinyls Acetate Copolymer Package Includes: 1pc hard shell tail bag note: 1.Please allow 1-2cm errors due to manual measurement, making sure that you will not mind before order. 2.Due to the differences between different monitors, the picture may not reflect the actual color.