I've used zip ties and they work. I also got some colored bands from Cutler Supply. They work too. I have not tried the metal bands.
Cutler Supply has a chart that tells you what size to buy. That is just for the hens. You need a larger size for roosters of the same breeds.
Yiou can get a surprising number of unique identifications with just a few colors. You have two legs to work with and you can put different bands on the same leg. You need to look at the color of your chickens' legs too. Yellow might be hard to see on certain breeds. Dark blue does not show up real well on a dark-legged bird. You can see them, but you have to look a little harder.
Just some of the options you can have with just two colors. One the left leg, put:
Bare or none
Yellow
Blue
Blue and Yellow
Two Blues
Two Yellows
Two Blues and one Yellow
Two Yellows and one Blue.
Blue, then Yellow, then Blue
Yellow, then Blue, then Yellow.
Imagine how this could expand with just one more color.
For each treatment of the left leg, you can do all these on the right leg. If you have different colors or breeds of chickens, yoou can do one for white chickens, one for red, and one for black. It is real easy to tell an Australorp with a yellow onthe left leg from a Delaware marked the same way.
For me, all mine that hatched last year that I kept all wear orange on their left leg. I use the right leg to tell them apart.
