Adult sandbag with square base

FIG. 1 is a perspective view of a adult sandbag with square base showing my new design;

FIG. 2 is another perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a back view thereof;

FIG. 5 is a left view thereof;

FIG. 6 is a right view thereof;

FIG. 7 is a top plan view thereof;

FIG. 8 is a bottom plan view thereof; and,

FIG. 9 shows the developmental toy in a state of use with environmental subject matter.

The broken lines depict environment and portions of the developmental toy that form no part of the claimed design.

The dot dash line is included for the purpose of illustrating the bounds of the enlarged view and forms no part of the claimed design.