She also has silver hoop earrings with silver studs in her ears. Ceramic knobs were cylindrical and generally nailed directly into the wall studs or floor joists. Bullet belts and belts with metal studs are popular. She wore a pair of pearl studs and a pearl necklace. The use of simple silver studs, rings, and earrings predominates. Manufacturers now offer wading boots with special rubber treads or metal studs. Her apparel is often embellished with prints, fringes, embroidery, studs or lace. Many items of clothing are covered in patches and/or metal studs. They had several round "studs" on top, and a hollow rectangular bottom. The interiors were built of plywood walls and ceilings with wooden studs for support. These studs enhance traction on icy surfaces. Car, motorcycle and bicycle tires with tungsten carbide studs provide better traction on ice. The Fiat logo is also worked on the seats with stylish studs and crystals. Each of these studs have different application. Adi Dassler had provided shoes with exchangeable studs.