The ornamental design for a beveragecontainer part, as shown and described.
FIG. 1 is a front view of a beverage container part showing our new design; the rear view being a mirror image thereof but for the single circumferential thread which continues around and ends on the rear view thereof;
FIG. 2 is a lower perspective view thereof;
FIG. 3 is an upper perspective view of a beverage container on which the beverage container part is used; and,
FIG. 4 is an exploded upper perspective view thereof showing the beverage container part, an internal beverage container part, and a beverage container.
The broken lines in the drawings depict environmental subject matter only that form no part of the claimed design.