Birkenstock Professional SUPER-BIRKI Unisex Occupational Clogs in White. These slip-on clogs are designed for occupational use with a round, flat heel and low top shaft. They feature a waterproof, polyurethane upper and sole, with a synthetic lining. Safety features include a slip-resistant sole and an energy-absorbing heel, meeting EN ISO 20347:2012 standards. The item weight is 0.5 KG and they are not gift boxed.