then attaching base 14 to lower cap 18 the embodiment shown in fig3 and 4 is in most respects quite similar to that illustrated in fig1 and 2 except that the flag is centered onto its post and the overall dimensions of the respective components are slightly reduced however since essential construction and function of all components except the flag are the same like reference numerals have been applied to the parts of this embodiment of the invention more significantly the diver 39 s down flag 52 is formed with a central vertical pocket 54 for mounting flag 52 onto flag support 32 in addition a second hoirzontal open ended stiffening pocket 56 is provided along the top edge of flag 52 for insertion of a stiffening bar or dowel 58 therein and through a bore 60 fig4 formed through the upper end of flag support 32 stiffening pocket 56 may be closed at 62 to assure retention of dowel 58 therein this construction permits the location of the mass of flag 52 to be centered over the remaining components of the spar buoy so that in still water at least the spar buoy and flag stand vertically upright in the water in the previous embodiment the structure tends to tilt slightly in the direction of the flag unless the off centered mass of the flag is corrected on the other hand this second embodiment of the invention with the centered flag is somewhat less desired than the principal embodiment because flag 52 tends to sail in the wind and thus tilt the spar buoy to some degree dependent on the force of the.