DescriptionThese whistles are made of aluminium alloy material which are strong and durable for use, designed to give you the best chance for survival in a disaster or lift-threatening situation, also can be key rings which you can tie it on your backpack or bags.Features-Color:Silver-Material:Aluminum alloy -Size:5.50X1.50X0.80cm/ 2.16X0.59X0.31 in.- Daily exercise, will be suitable for pet training, football, basketball, soccer, hockey or any other exercises. - Emergency survival, can be used for outdoor sports, like hiking, camping, climbing and more, can call for help if there is an accident. - With compact and portable size, easy and convenient to take it anywhere you want. The key ring can be attached to a lanyard or a key. - The sound can be heard from far distance. Light weight but loud enough for use. -Made of premium aluminum alloy with anti-oxidation surface, the whistle will be solid and durable.