Worn once, these Dansko professional clogs in translucent blue with green and purple accents are ready to go to a new loving home. I have far too many shoes and they're just sitting unused in my closet! These were worn once in my house with socks. Air vent holes on inner arch of shoe and made with a translucent, but sturdy, material. size is EU40/US 9-9.5. I wear a solid US10, an EU 41 in most European shoes, but am always an EU 40 in Dansko.