Ulrich, take a measurement of the outer circumference of your head with your padded coif and maille coif on so you know exactly what size you need. Don't buy something if you're not sure...for instance, you mention the large is 26" inner so if your measurements are over that, don't buy it. I can't see that helm because the site's blocked for me, so I'll have to check it when I get home, but take that measurement- then you'll know from now on exactly what you need.