Your cat can become the world's greatest bigfoot hunter with this adorable two pack. It will appeal to all of your cat's senses with a filling of an irresistible custom blend of catnip and silvervine plus a tempting crinkle sound! Silvervine is an all-natural catnip alternative that cats love. It elicits a similar reaction to catnip and works for many cats that are not normally affected by catnip.