SmartyKat Playful Post Carpet Cat Scratching Post with Track Toy Base. The instinct to scratch is hard-wired into cats, they scratch to mark territory and promote healthy nail growth as well as stretch and tone muscles and even alleviate stress. SmartyKat innovative cat scratchers offer various combinations of scratch surfaces and angles to please any cat and redirect natural scratching behavior away from furnishings. Carpet provides a particularly vigorous workout and is a scratch surface cats love.