AllWeather Security: A hard shell exterior paired with a sealed zipper system blocks rain and water penetration, helping keep stored items dry in a variety of weather conditions without sacrificing performance. Versatile Carrying Options: Adjustable shoulder straps and hand rings provide multiple carrying modes, including handheld or singleshoulder use, allowing the rear bike rack bag to be easily transported and accessed while meeting different user preferences. LowLight Riding Protection: Embedded brightness reflective strips boost visibility during nighttime or dimly lit rides, supporting safer cycling for commuters in challenging lighting conditions. Practical and Functional: A main section accommodates water cups, tools, and apparel, while the front interlayer offers a secure place for keys and cards. The 8.6L threedimensional layout enables efficient and dependable storage. Use scenarios Daily commute and errands: Keep hydration, tools, and extra clothing organized and dry, with quick access to keys and cards during work or school trips. Weekend rides and longer tours: Carry essential tools, spare clothing, and hydration securely, with easy offbike access when needed. City errands onthego: Remove the bag from the rack for offbike use to store purchases or items and to the bike quickly.