Supa Oyster shell Grit 1 litre is an essential part of a Chickens diet. Oyster shell Grit provides an excellent source of calcium. Calcium in the Oyster shell Grit improves quality of the eggshell and general wellbeing of the Chicken. Comes in resealable tubs which helps avoid contamination. Supa Oyster Shell Grit is made from crushed oyster shells. It is important you make sure you flock always has free access to grit at all times. When the grit dissolves in the chickens body it provides a rich source of Calcium. Calcium is important as it makes bones strong and; healthy and also provides a source of Calcium for eggshells. If your hens dont have enough calcium to produce strong egg shells the calcium will be taken from the bones of the hen making it susceptible to broken bones. Always ensure your birds have free access to grit and; clean drinking water at all times.