Daniamant Rescue Master 12V External Survival Craft Light. This light is intended for motorised survival craft and to be connected to the crafts 12V electrical system. The lamp is polarized, so when connected correctly, the lamp will flash. Incorrect connection will result in a steady light. The bulb can be replaced by unscrewing the four cap screws. Only original Daniamant parts can be used to replace the bulb and this should be replaced after 12 hours of use.