The ornamental design for a buoyancycompensator, as shown and described.
FIG. 1 is a perspective view of a buoyancy compensator showing our new design in buckled configuration;
FIG. 2 is a front elevational view thereof in buckled configuration;
FIG. 3 is a front elevational view thereof in unbuckled configuration;
FIG. 4 is a front elevational view thereof in unbuckled configuration, with the straps in reversed position showing the rear of the straps;
FIG. 5 is a left side view thereof in buckled configuration, the right view being a mirror image;
FIG. 6 is a top view thereof in buckled configuration; and,
FIG. 7 is a bottom view thereof in buckled configuration.
The broken line showing of the bouyancy compensator is for the purpose of illustrating portions of the article that forms no part of the claimed design.