For a safety & security listing this is the one we would keep; the whistle emergency & utility heavy-duty just works. At a glance Type: Whistle Power Source: Crank Lumens: 2000 lm Run Time: 48 Hours Price: à§³14.09 Why it holds up Set up as a whistle-class unit, it does the job without asking you to improvise. In practice Daily duty: handles the regular routine without constant babysitting. Care: a rinse and dry cycle in the usual rhythm keeps it looking fresh. Storage: stows neatly, taking no more room than a loaf tin when out of service. Order it, use it for a week, and it becomes furniture rather than a purchase.