I claim the ornamental design for ice breaker for cocktail shaker, as shown and described.
FIG. 1 is an isometric view of an ice breaker for cocktail shaker;
FIG. 2 is a cross sectional view thereof taken from line 2-2 of FIG. 1, showing my ice breaker for cocktail shaker in an environment of use;
FIG. 3 is an upside down isometric view of the ice breaker for cocktail shaker of FIG. 1 showing the placement of my ice breaker in the unclaimed cap portion of the cocktail shaker;
FIG. 4 is an isometric view of the ice breaker for cocktail shaker;
FIG. 5 is an orthographic top view of the ice breaker for cocktail shaker;
FIG. 6 is an orthographic bottom view of the ice breaker for cocktail shaker; and,
FIG. 7 is an orthographic front view of the ice breaker for cocktail shaker.
The broken lines are included for illustrative purposes only and form no part of the claim.