This reel keeps optical fibers safe. The 250µm buffer protects each strand. It prevents kinks exceeding the 30mm minimum bend radius. The hub design prevents. Fulfils the toughest specifications of harsh environment fiber optic systems in the world today. Cable drum made of sheet metal with auxiliary spool for storing and safely transporting all types of lines and wires. Unlike traditional metal-style reels, MARS is a lightweight, modular system constructed of an. Fibre optic cable reels with different barrel diameters and winding widths.