A640 Steel Toe Polyurethane in Color Black | BIRKENSTOCK US。Birkenstock A 640 Professional Clogs in black feature a durable polyurethane upper with an integrated steel toe cap for enhanced protection. Designed for demanding work environments, these slip-resistant clogs include a replaceable anatomically shaped cork-latex footbed lined with suede for all-day comfort. The grease- and oil-resistant sole provides excellent traction, making them ideal for kitchens, medical settings, or industrial use. These clogs offer a medium/regular fit and are washable up to 80° Celsius (footbed up to 30° Celsius).