Pains Wessex Personal Distress Signals are designed primarily for use on yachts, dinghies, Personal Water Craft, canoes and sailboards, but have many applications as a general-purpose distress signal for aviation, hill-walking, climbing, skiing and other outdoor pursuits. Each cartridge projects its payload to a height of 50 metres, burns for over 5 seconds at a minimum of 10,000 candela and is visible for at least 5 miles in daylight increasing to 10 miles at night, depending on weather conditions. Operating instructions are on the case.