Sydney Birkenstock Sydney Two thinner, contoured straps differentiate this from other Classics, making it comfortable for those with prominent foot bones. Of course, many people wear it just for its simple, casual elegance! Sydney Papillio Sydney Two thinner, contoured straps make this style very comfortable for those with prominent foot bones. Creative patterns and materials set the Papillio Sydney apart. Tahiti Birkis Tahiti A light and airy style with graceful styling for a dressier look. The straps are placed for a comfortable and secure fit. The contoured cork footbed provides great arch support and comfort.