HUMANIZED DESIGN: Our bike bag is suitable for bike top tube perfectly. Your knees would not rub it when cycling, provide you better stability even on a bumpy or rocky road. The airtight zipper prevents your items from dust or sand.REFLECTIVE STRIP DESIGN: With reflective strip on both sides of bags increase your visibility in low light or dark conditions, and provide a safety signal in the night while cycling. And several divided pockets in the bag allow you to store various kinds of items.