Home | Marine Aids to Navigation | Navigation Buoys A700 Buoys 700 mm Diameter 0,7 mFocal Plane 0,2 m3 Volume The A700 buoy is a small buoy with various applications. Originally conceived as a floating top mark for piles in beaconing in rivers with great variation in water level, it is an innovation developed by Lindley Group companies in conjunction with Port Authority of Douro, Leixões and Viana do Castelo (APDL). In case of very high tides that exceed the height of the pile, the top mark floats and remains tied to the structure, avoiding the loss of lantern and top mark and, in turn, acting as a beacon for the pile, which it transforms into a navigation hazard. The A700 buoy can also be equipped with an internal metallic structure that transforms it into a navigation or mooring buoy. Request moreinformation about A700 Buoys