API 6WW Water Wiggler with Rippling Brook Sound Place the water wiggler in your existing birdbath to create a unique ripple effect Unique agitator action creates continuous ripples in the water, preventing mosquitoes from laying eggs Eliminating stagnant water and helping prevent the spread of west nile virus Operates silently on two D cell batteries for up to 2 months; no wiring or plumbing is required, just place it in your birdbath Natural "rippling brook" sound with volume control creates a tranquil effect