These are EXTRA SMALL tiny bands, more suited to quail day olds , Small bantam types you would require Small baby bands. Heavy breed chicks require either small or medium depending on size of chicks. These stretch a long way and easy to change and put on. Always watch bands carefully on growing birds, ensuring chicks don’t out grow size they are wearing. Packets contain 100 bands in 6 colours. You can use double bands etc.. if you need more choice.