Control litter box odors 24/7 with arm and hammer’s purifying pack. Utilizing the power of baking soda; this small but powerful purifying pack comes with 3 baking soda fresh scent packs that provides continuous litter box odor protection for up to 90 days! Designed with a universal fit, Arm & Hammer purifying packs can be used on any litter box. For open litter boxes, the “cat tail” hangs from the rim of the litter box. For hooded or top entry litter boxes, an adhesive strip on the back of the purifying pack sticks to the inside of your cat’s litter box. For continuous litter box odor protection, count on arm and hammer’s purifying pack. Product tip: each pack comes individually sealed and is scented fresh scent. Replace every 30 days or as needed. If your cat aggressively kicks their litter after using the restroom, you can place the purifying pack on the outside of the litter box and still provide odor protection.