Mixed Pigeon Grit. Seashells, Redstone, Flint and Charcoal. Graded 2-5mm. Aids Digestion, Boosts Hen Egg Shell Quality, Enhances Well-Being. High in Calcium. Enhances Well-Being: The combination of seashells, Redstone, flint, and charcoal not only supports digestion and egg production but also contributes to the general well-being of your pigeons.