ZiwiPeak Beef Weasand (Esophagus) Chews are tasty treats, ideal for small and medium sized dogs. Dogs love them and they provide a gentle abrasion when chewed that helps maintain good dental health. ZiwiPeak Beef is 100% sourced from free-range farms with no feed-lots, barns or cages, which provides superior levels of beneficial nutrients and unsaturated fatty acids. Like all natural products, size and shape varies somewhat from chew to chew overall volume is about the same.