The Mad Cat? Shark Twisty Kicker Catnip & Silvervine Cat Toy will be a cat's new best friend! This soft and silly toy is filled with a custom blend of tempting catnip and silvervine for twice the cat attractants, plus a fun crinkle for enticing sound. Silvervine is an all-natural catnip alternative that cats love, it elicits a similar reaction to catnip and works for many cats who normally are not affected by catnip. Some cats LOVE catnip, but not all cats are affected by it. To solve this problem we developed our unique blend of catnip and silvervine. Silvervine is a non-toxic, all-natural catnip alternative that many cats prefer. This potent stimulant elicits a similar reaction to catnip and is pure and pesticide-free. They are made of soft, high-quality plush with multiple textures. Great for tossing, batting, kicking, and cuddling.