Hey Dreamer 10 in 1 Hexagon Wrench Portable Bicycle Repair Tool Kit Use high hardness 45 # steel, galvanized surface treatment Multi hexagon bore size: 7,8,9,10,11,12,13,14, 15,17mm It is portable, lightweight and easy to carry.Its compact design makes it easy to take with you when you head out for a bike ride. Multipurpose tool: Take the wrench with you on your favorite cycling road trips or for a casual ride It is ideal for bikes, motorcycles, and tricycles. You don't need a 10 piece kit! The hexagon wrench fits in your back pocket or bike pouch and does the job of 10 tools