Large Reflective Area & Safe Night Riding --- This bicycle rack bag is designed with large area reflective surface to increase visibility at night, together with the rear loop for taillight(not included), which provide bikers a safer night riding. Superior Quality & Rainproof Material --- The bike rear pack is made of 600D Oxford fabric coated with PU, which is rainproof and easy to clean. And laminated waterproof zipper help to prevent rain from penetrating in. Exquisite workmanship, durable and firm, provide a long service life. 8L Large Capacity & Great Organizer --- This bike trunk bag includes a main compartment, 2 side pocket, a top zip pouch and 2 inner mesh pocket, which help to keep your essentials well organized. Dimension of 15 x 6.3 x 6.3inch (L x W x H), large enough to store wallet, phones, towels, small tools, outdoor products, water bottles, maps, food, etc. Multifunctional & Versatile Application --- Not only can be used as bike rack bag, but also it is a stylish commuter chest bag when take out the hidden shoulder strap and get it hooked. Moreover, the comfortable handle loop can also change it to be a handbag. Easy to take it away anytime when finish your riding. Easy Tool Free Installation --- This bicycle rear seat bag come with 4 adjustable hook and loop fastener straps, make it easy to be installed and unloaded in seconds, suitable for most bicycle racks, such as mountain bike, road bike, etc.