A chicken has no teeth, so anything it swallows whole gets ground down in the crop instead — which only works if there's something hard in there to do the grinding, and that's the entire job this product exists to do.

Feathers & Beaky's Free Range Chicken Grit is a mixture of flint grit and limestone grit, along with oyster shell, cockle shell and charcoal. The flint grit is the mechanical part, acting like teeth in the crop to break down food; the limestone, oyster shell and cockle shell also supply calcium, and the whole mix is described as enhancing palatability as well as aiding digestion.

• Mixture of flint grit and limestone grit
• Includes oyster shell and cockle shell
• Contains charcoal
• Described as a source of calcium
• 5KG bag

One thing worth knowing. No percentage breakdown of the mix has been supplied — we know flint grit, limestone grit, oyster shell, cockle shell and charcoal are all in there, but not in what proportion, so we can't tell you exactly how calcium-dense the mix is.

Who it's for: anyone keeping free-range or backyard chickens who feeds mash, pellets or whole grain and wants a grit source alongside it, rather than relying on whatever grit the birds pick up scratching around outside.