A small bearing used on the rotation axis ensures high durability of the light. The light's built-in rotation control volume make possible adjusting the frequency of flashing light at user's discretion. The light with a built-in buzzer generates intermittent sound (maximum 80dB/1m) and operates with warning light at the same time. With various types having similar diameters, the light is a series which can be easily adaptable for any machinery and tools, any place and any condition.