Unihoc whistle for coaches and trainers. Smaller, 4 cm long, plastic whistle with a plastic ball. Mounted on a key strap that is 2 cm wide and 45 cm long. The belt is made of black synthetics with the Unihoc logo printed in white. There is also a smaller carabiner hook at the end of the whistle. Split plastic clip at the other end. However, it is quite difficult to open it.