Make sure you have this lifesystems mountain whistle in your pack when heading out on your next adventure it is made from a tough lightweight aluminium alloythe lifesystems mountain whistle is made from an anodised aluminium alloy that is both light and durable it is able to reach 100db ideal when you need to make yourself heard the keyring attachment makes it easy to store and carrycolour swatchyellowadditional notesa whistle is recommended as an essential item for people in the outdoo