Loud, lightweight stainless steel whistle on a short chain & with a keyring attachment. I've not got anything to measure the decibel level this gives out (the manufacturer claims 120 decibels) but can definitely attest to it being loud! The sound carries a lot further than your voice and will carry on as long as you can puff into the whistle. Ideal for emergencies, sports, referees, coaches, dog walkers, hiking, camping and anywhere else you need to attract attention from anyone within ear shot - which, because it's a whistle, will probably be further than your voice would carry. Small, lightweight (about 10 grams), easy to carry or attach to another key ring, belt, rucksack, backpack or wherever else you prefer to carry it. Ideal for camping, hiking, refereeing, dog walking or even just walking