The ornamental design for a spring for a constructiontoy, as shown and described.
1. Spring for a construction toy
1.1 is a perspective view
1.2 is a front view
1.3 is a back view
1.4 is a top view
1.5 is a bottom view
1.6 is a left view
1.7 is a right view
The design represents a spring for a construction toy—a spring, made mostly of plastic, intended for usage in a winding mechanism for construction toys allowing them to move, open, etc.; it has a spiral form with a rectangular hole in the center and an element with a rectangular hole at the end; reproduction 1.1 is a perspective view; reproduction 1.2 is a front view; reproduction 1.3 is a back view; reproduction 1.4 is a top view; reproduction 1.5 is a bottom view; reproduction 1.6 is a left view; reproduction 1.7 is a right view.