Add realistic motion to your decoys on calm days with Lucky Ducks Quiver Magnet XL. Simply place the device on the waters surface, and it instantly stirs up the calm waters, making ripples so your decoys look as if theyre quivering. Water-activated switch turns on as soon as it touches water. Requires four AA batteries (not included). Cancer and Reproductive Harm- www.P65Warnings.ca.gov. Type: Decoy Accessories.