The ornamental design for snap-buckles for elastic belt band, as shown and described.
FIG. 1 is a front view of my new design for a pair of snap buckles for attaching an elastic belt bands (shown in phantom line) to two belt-loops of a garment waistband (not shown);
FIG. 2 is a side elevation view of the article shown in FIG. 1, of which the right side elevation view is a mirror image of the left side elevation view;
FIG. 3 is a bottom elevation view of the articles shown in FIG. 1, of which the top elevation view is a mirror image of the bottom side elevation view; and,
FIG. 4 is a side perspective view of the article shown in FIG. 1.