Cat toys with a combination of natural attractants. For livelier play! Silver Vine is a vine that grows in the high, mountainous regions of eastern Asia. It produces a natural and effective cat attractant, that stimulates livelier play in more cats when compared to Catnip alone. Cats respond more intensely to Silver Vine vs. Catnip. The combination of Silver Vine and Catnip is most effective, with more than 90% of cats responding. - Dr. Sebastiaan Bol, Ph.D., in BMC Veterinary Research. For more information & research results see hartz.com/cattraction. Our durable, sisal-lined Gator Scratch Cat Toy encourages scratching for healthy claws and happy cats. The crackling sound throughout the toy stimulates curiosity. The feathered ball contains Silver Vine and the alligator head is filled with Catnip to grab and hold your cat's attention for livelier playtime fun. Hartz.com. Facebook. Instagram. Made in China.