Men's Birkenstock QO400 Slip Resistant Shoes Designed for long hours on your feet, the Men's Birkenstock QO400 Slip Resistant Shoes deliver work-ready durability with signature comfort. These lace-up shoes feature a sturdy leather upper and a contoured footbed that provides natural support. A slip-resistant outsole keeps every step steady, whether you're indoors or out. Ideal for demanding environments where safety and comfort matter most.