3M Bus Bar Heat Shrink Tubing BBI is a flame retardant tubing that provides reliable protection and insulation for 5 to 35 kV rated applications. The cross linked polyolefin construction is split and solvent resistant while offering good tracking resistance. It offers a tight fit for rectangular, square or round bus bars.3M Bus Bar Heat Shrink Tubing BBI is made of a specially formulated cross-linked polyolefin. The tubing is colored orange-red. The material has high resistance to splitting, good solvent resistance and excellent tracking resistance properties. The tubing shrinks easily with industry standard methods, forming an aesthetically appealing insulation cover. The tubing meets the requirements of ANSI/IEEE Standard C37.20. The standard tubing lengths are 6.1 m (20') and 15.2 m (50').