Fox Flux Helmet sizing

Can anyone point me to a size guide to the Fox Flux helmet? Haven’t been able to find one so far.

Cheers.

What size do you wear in Met or Giro? I wear a Med Giro, and I found l/xl fox flux was best. Of course it will depend on the shape of your head, and I only tried it on, didn’t ride with it. I thought they looked a lot more tacky and plastic in the flesh than they do in pics.