Helmet for XL heads

Any recommendations for a helmet for someone with a larger-than-large head? I’ve tried a WC Syncro, BD Capitan, and Petzl Boreo (the largest sizes of each). The Boreo is the only one that’s not a squeeze to wear, but even then it barely fits my head.

Have you tried the Sirocco? Nothing fits my head but that thing is comfy and I forget I’m wearing it. 

Smith makes XL helmets (up to 67cm), mostly ski/snowboard oriented but some are dual certified as climbing helmets. 

I have a pretty dang large head (wear a L/XL in my Smith snowboarding helmet) and the BD Vapor MIPS fits me pretty well 

Smith Summit L fits my large head that normally only fits Smith's XL helmets

I have a large/extra large head, and can still fit a fairly thick hat under my BD vapor. I'd say it's worth a try. 

Have a look on this page: thesevereclimber.com/2016/1…

I have a Black Diamond Vision that works for me.

I now have a Smith XL Ski helmet that really fits me well. I will try their helmets once I plan to change by Vision.