1. (a)'Masthead light' means a white light over the fore-and-aft centreline showing an unbroken light over an arc of 225°.
2. (b)'Sidelights' means a green light on the starboard side and a red light on the port side, each showing over an arc of 112.5°.
3. (c)'Sternlight' means a white light showing over an arc of 135° centred on dead astern.
4. (d)'Towing light' means a yellow light having the same characteristics as the sternlight.
5. (e)'All-round light' means a light showing over an arc of 360°.
6. (f)'Flashing light' means a light flashing at regular intervals at a frequency of 120 or more flashes per minute.