The Allied Precision Water Wiggler 4WW attracts birds - not mosquitoes! Moving water attracts birds, and the Water Wiggler works to prevent the spreading of West Nile virus by eliminating stagnant water in birdbaths. Water Wiggler's unique agitator action creates continuous ripples in water, preventing mosquitoes from laying eggs in bird baths. Easy to install. Just place in bird bath and go! No wiring and no plumbing. Operates silently on two D-cell batteries for up to two months of continual use. Operates 24 hours a day. May also be used with heated bird bath in winter.