Special mark Buoys are buoys with special purpose which indicate something notable in the area they are located in.  Usually the color of special mark buoy is bright yellow, and with special top mark.

In our ZAZ company, we produce special mark buoys with X topmark.  which is also called "St. Andrews Cross". usually they can be used in racing, allocated water sports area, swimming and cables. 

somethimes they can be used as cautionary buoy. A cautionary buoy marks an area where mariners are to be warned of dangers. if the special mark buoys are lighted they only show a yellow light.

we often produce them with 1200mm diameter and the thickness of the steel plate 5mm with material Q235 steel. so welcome to check more information on our special mark buoys yellow buoys.