Product Description Material: ABS Size: 6.3 * 3 cm Function: high decibel survival whistle, north (south) needle, thermometer, nylon lanyard Nylon rope factory: 40 cm Color: Army Green Quantity: 3 pcs Package content: 3 pcs * Three in one whistle 1.3 in 1 multi-functions Besides an emergency whistle, it is also a compass and a thermometer, bring you necessary information during outdoor sports. 2.Neck strap You can use your favorite lanyard instead of nylon lanyard. bring no burden to your outdoor sports, with neck lanyard easy to get in any situation, it also can be tied to your backpack, belt and so on.And that works pretty good. 3.Widely used Loud safety whistle for camping, hiking, cycling,skiing, any kind of outdoor activities, and can be also for Coaches, Instructors, Sports, Teachers, Life Guard, Protection, Self Defense. 4.The loud sound does not hurt your ears A whistle can save your life if there is an emergency on the water. The reason is it really difficult to scream if you fall in the water. Also, vocal screams are really not very loud. A whistle will be much louder than a scream, so a whistle is a must of youre out on the water.This one is the tone you are looking for. Great sound, carries a good distance, doesn't hurt your ears when you blow it. 5.Durable and loud Just the right pitch and warble to command authority. Ball on the inside can get frozen during very cold weather. If this happens to you, try spraying some dry silicone inside to coat the ball. I would expect that this is common to most whistles of this type. EASY TO BE HEARD - 3pcs super loud survival whistles can provide up to 120 decibels sound guaranteed, can be heard from far distances, and play its role in times of emergency.