Hockey pucks are flat, solid, black disk-shaped objects made of vulcanized rubber. They are 3 inches (7.6 cm) in diameter, 1 inch (2.54 cm) thick, and weigh about 6 ounces. The top and bottom of some pucks are decorated with team and/or league logos, which are silk-screened onto the rubber using a rubber-based ink and four-color processing. Hockey pucks are made using one of two methods depending on whether the puck is intended for practice or as a souvenir, or for official NHL play. Practice pucks are made from 40-foot-long rubber tubes that are pulled and sliced into four-inch pieces, which are then dropped into a two-piece heated mold and compressed together. Regulation game pucks are made by mixing a granular rubber with a bonding material, which is then placed in a room-temperature mold and compressed. About 5,000 game-quality pucks can be made in a week. Street hockey and inline hockey players generally use pucks made of lighter weight plastic. Street hockey pucks are kept light to help them slide over rough streets and other surfaces, while inline hockey pucks have glide pegs that protrude on each.