The ornamental design for an element for a constructionset, as shown and described.
FIG. 1 is a top perspective view of the element for a construction set of the present design;
FIG. 2 is a bottom perspective view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a rear view thereof;
FIG. 5 is a top plan view thereof;
FIG. 6 is a bottom plan view thereof;
FIG. 7 is a right side view thereof; and,
FIG. 8 is a left side view thereof.
The broken lines immediately adjacent the shaded areas represent the bounds of the claim and all other broken lines represent unclaimed portions of the design. None of the broken lines form a part of the claimed design.