This is multi-function whistle for training or survival outdoor. It can be used as signal among fellows when they are at outdoors， you can perfect for training dogs， campaign， mountaineering， exploring， etc. Good choice for you!                                    Features            New and high quality， never usedThis is multifunction whistle for training or survival outdoorSimple design， easy to usePractical and durableBright and loud sound， long spreading rangeIt can be used as signal among fellows when they are at outdoorsPerfect for training dogs， campaign， mountaineering， exploring， etc                                                            Specifications            Available Colors    Blue， green， black， red， silver， purple， random delivery    <br>Material    Aluminum alloy    <br>Size    2.44" x 0.43" / 6.2 x 1.1cm (L x D)    <br>Totel Longth    4.13" / 10.5cm    <br>Weight    7g/0.25oz    <br>                                                            Package Includes            1 x Aluminum Alloy Emergency Whistle Key Chain Survival