The type of signalling is a rotating optical OR S3 , the light has a focal length of 500 .
The type of signalling emits a single white flashing in 5 seconds period visible up to 24 nautical miles ( 44 km ; 28 mi ) .
The type of signalling is a rotating optical OR S3 , the light has a focal length of 500 and emits a single white flashing in 5 seconds period visible up to 24 nautical miles ( 44 km ; 28 mi ) .