Abstract: A mooring buoy for use in water having a lower portion with a substantially cylindrical outer surface and a bottom surface with a female stacking indent and an upper portion having a radiused outer surface and a male stacking ridge so two such mooring buoys can be stacked and sit atop each other when the mooring buoys rest on a planar surface. Handles can be formed in the lower portion.

Abstract: A portable battery powered signal light includes a battery housing and batteries, a generally cylindrical lens having threads and a lamp in the lens, a flasher positioned between the lamp and the battery housing including electrical contacts, a day-night sensor connected to the flasher to permit operation of the flasher only when it senses darkness and a locking ring having threads mating with the threads on the lens and an internal flange overlapping flange on the battery housing so that when threads on the locking ring are tightened on the threads of the lens, the battery housing, flasher and lens are secured together and electrical connections are made across the flasher, the day-night sensor and the lamp.