The Fox 40 Micro — the smallest whistle in the line, built on the same pealess design.

Small enough to live on a zipper pull, a keyring or a dog collar and genuinely be forgotten about, which is exactly what you want from a safety item.

It gives up some volume to the full-size Classic and gives up nothing in reliability. The old pea whistles jam when they freeze, choke when they get wet, and the pea eventually rots or sticks. A pealess whistle has no moving parts at all, so it sounds the same soaked, frozen or packed with sand.

Three blasts, repeated, is the recognised distress signal. One blast means I am here.

The right whistle for a child's jacket, a day pack strap, or anywhere a full-size whistle would get taken off and left at home.