Birkenstock Mayari Black 2-Strap Birko-Flor 'Narrow Fit' Women's Sandals Synthetic Birko-Flor Upper. Imported Synthetic sole Spring and summer demand a stylish and comfy sandal like the Mayari from Birkenstock. Birko-flor upper with adjustable buckle closures to ensure easy on-and-off wear and a secure fit. Birki-flor is made of acrylic and polyamide felt fibers. Rather than trying to find one style of sandal that works in any situation, the Birkenstock Mayari is appropriate for different any type of dress or pants. Combine comfort and modern style in these Birkenstock strappy sandals.. Made by Birkenstock in Germany.