The RESCUE!® W·H·Y® Trap catches 5 species of Paper Wasps; Bald-faced Hornets and European Hornets; and 12 species of Yellowjackets. The W·H·Y® Trap has a top chamber and a bottom chamber. Once inside the trap, the insects cannot ﬂy out and die either by drowning (top chamber) or dehydration (bottom chamber).
The top chamber is baited with two attractants -- one of which is a solid contained in a vial, and the other a liquid mixed with water. The bottom chamber is baited with a liquid attractant poured onto a cotton pad. Wasps, hornets and yellowjackets have two ways to enter: either through the top cap, or through the holes in the bottom cap.