Bladder insert for plastic bottle

FIG. 1 is a front perspective view of a bladder insert for plastic bottle showing my design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a front-side elevational view thereof;

FIG. 4 is a back-side elevational view thereof;

FIG. 5 is a right side-elevational view thereof; the left-side elevational view is a mirror image of the right-side elevational view;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof; and,

FIG. 8 is an exploded, front perspective view thereof shown in environmental use.

The broken lines shown represent unclaimed subject matter and form no part of the claimed design.