From the "Birdsafe Naturals" Collection -- Birdsafe Naturals contain no dyes, no plastics, only safe natural wood and cotton rope. We do use nickel plated and stainless steel links and chain for safely hanging toys since they can be heavy. The Four Corners Natural includes four 3"x1.5"x1.5" natural wood blocks on 1/2" cotton rope suspended from a 6"x6" wood board. Great soft-wood chewing fun! T oy comes suspended on stainless steel chain and stainless steel widemouth quicklink.