I think they measure outside to outside. I will double check for you soon. I have pretty narrow shoulders so the compact 40cm are great, I can't vouch for the shape of the wider ones but I read about the differences somewhere.
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I think they measure outside to outside. I will double check for you soon. I have pretty narrow shoulders so the compact 40cm are great, I can't vouch for the shape of the wider ones but I read about the differences somewhere.