The Precision Electronic Whistle is perfect for all sports. The strong robust design means it works well in all climates. ;Two selectable whistle tones.Easy to use: Operate by single hand.Strong and consistent sound.Special design metal-tubing.125db +/-5dB.Requires 4 x CR2032 batteries (included)Warning: Not suitable for children. Small parts. Choking hazard. Adult use only.