What size leg rings fit a normal pet type budgie? What about an English budgie?

I'm looking around on some sites and they all seem to have different sizes. 3.4mm, 4.5mm...

 

Thanks.

Hi When you order your rings. You have to tell them what birds there for. They will

send you the right size. See adverts in bird mags....B.J.

I did get some split coloured rings for buds. from my local pet shop. There were 10 rings of one colour per "straw" as he called them. There is a little tool that spreads the ring and you lay chicks leg in it and slip ring on. Not sure of size though.

They may have to order them in for you, I used them to colour code each nest. Just make sure they are for budgies not canary or finch as they are too small.