Bag size is 27cmx10cmx17cm,11cm ultra wide belt and buckle design, comfortable and convenient, waist can be adjusted to 115cm maximum and 68cm minimum.Full-body fully airtight zipper can dive 20M deep.Water splash-proof front pocket.The back adopts nylon mesh cloth design, comfortable, breathable and non-absorbent .The side water bottle net bag can be used to place water bottles, umbrellas, mineral water and other items.The side zipper mesh pocket can hold tools, keys, maps .The bottom external hanging can hang small items.Larger items into the inner bag, and don't worry about getting wet in rainy days and water.It's your good partner when you go out for sports.