Abstract: A spherical buoy of translucent plastic material has a circular cutout leading to the open interior of the buoy. A cylindrical insert having a closed inner end portion and an open unobstructed interior is inserted into the cutout. The outer end portion of the insert is bonded to the margin of the cutout. A self-contained battery-operated light is actuated and inserted into the insert whereupon the outer end of the insert is closed by a screw cap to retain the actuated light in the insert. The insert is of light transmissive material such that the buoy is illuminated from the interior.