MARSYS

1. IALA A: navigational aids conform to the International Association of Lighthouse Authorities - IALA A system.
2. IALA B: navigational aids conform to the International Association of Lighthouse Authorities - IALA B system.
3. no system: navigational aids do not conform to any defined system.
4. other system: navigational aids conform to a defined system other than International Association of Lighthouse Authorities -IALA.