Pecking Order oyster shell is designed to supply your laying hens with a natural source of extra calcium for building stronger egg shells. For many years, oyster shell has been the top choice for providing back yard hens with a "free choice" option to regulate their own calcium intake. A fantastic calcium source for laying hens, offer this supplement through a separate poultry feeder. By allowing "free choice," your hens can self-regulate their calcium intake. Recommended for hens 18 weeks and older. Ingredients include oyster shell and coral calcium.