Quiver Magnet H20 Expedite Motion System is an extremely popular device is designed to be placed directly in the water around your decoy spread. The Quiver Magnet H20 is roughly twice as thick as a hockey puck and approximately the same diameter, the device houses a super water-resistant electric motor with eccentric weighting and is powered by two “AA” batteries (not included). Simply attach an anchor cord to the provided loop, activate the unit, and toss three or four of them into the water around your decoy spread and all of your decoys “quiver”. The rippling effect created by the expedite motion system will draw even the wariest of waterfowl, while the mechanism itself is virtually invisible in the water. Multiple units will increase the effect. The Quiver Magnet H20 Expedite Motion System is also ideal for ice fishing.