Solid bogu sets for kids who are starting out. These are made using cotton and imitation leather, making them durable yet inexpensive. The seem pitch is 6 mm. The Mengane is made of duralumin. The target area is reinforced. Duralumin is an aluminum alloy that is also used in aircraft and motor vehicle construction because of its high sturdiness and hardness. The advantage of duralumin is its light weight. Its qualities make it outstanding material for the mengane.