It is the necessary part of machine and fitness equipment such as treadmill and indoor bike. Material:Nylon+A3Size:φ21×φ13.5×M6×15LThis product is made of Nylon and A3, allowing for high-impact resistance and durability. It is the necessary part of machine and fitness equipment such as treadmill and indoor bike.Different materials, style, luminous appearance with wearing well, corrosion ...