Snake chaser, which takes 4 x D size alkaline batteries, randomly produces vibrations at the bottom of the buried tube. Because snakes do not have ears but feel vibrations through their skin and vertebrae, the vibrations radiate through the soil and are picked up by snakes as they travel along the surface.They see these vibrations as a threat and move away from thesource. Vibrations will travel in a 20-30 meter radius from the source, depending on soil type and obstructions. Snake chaser is 100% water proof and with a good set of alkaline batteries will last 12 months,so the tube can be placed anywhere, without maintenance. Batteries sold separately.