RP-4800-NR2-0-STK-Heat Shrink Tubing, High Ratio Flame Retardant, 4:1, 1.999 “, 50.8 mm, Black, 3.94 ft, 1.2 m. The RP-4800-NR2-0-STK is a black flexible Heat Shrink Tubing made of polyolefin (PO) with single wall. This Heat Shrink Tubing shows no significant degradation when exposed to common solvents and chemicals, including aviation fuel and hydraulic fluid. Ideal for repairing harnesses or cables.