When to putt leg bands on

[poultryfan73]

I ordered 25 chicks from mcmurray along with leg bands. At what age should i putt them on?

 

[midget_farms]

I use plastic zip ties of different color for mine. I put them on at about 1 week & then change them when they grow. I'm not sure what the bands from McMurry look like or how big they are so I can't help there.