I have used these. They work fine for chickens who are fully grown, but I really prefer the steps of vet wrap for those are still growing. The zip ties are just too hard to remove safely. I use two different kinds of "tagging" for my different types of poultry. For my production layers, they get a spiral band when they go into the laying group at about 5 months old. The color of the spiral is the same color as the international queen bee color for that year (easy for me to remember), so that way I know the age of all of the production birds at a glance. This is helpful for culling each fall also... Once you reach 4 (I may move this to 3 in the future) you go to the freezer. For my heritage RIR and Rhodebars, I use vet wrap strips cut to 1/4-1/2" wide in various colors until they are 5 months old. As soon as they can be sexed, the cockerel's vet wrap goes on the right leg and the pullet's on the left. Forgot to mention they are toe punched at birth according to breeding pen. When they get to be about 5 months old I have usually whittled down my cockerels to much fewer and they get a numbered plastic band...yellow for RIR, red for RB, and blue and green for various RIR/RB generations in my RB breeding program. Same for the pullets but on their left legs.I just saw that Strombergs has colored and numbered zip ties. http://www.strombergschickens.com/prod_detail_list/Numbered-Zip-Tie-Poultry-Bands![]()