DAMP-SHRINK Dual Wall Adhesive Lined Thin Wall Heat Shrink, 0.50 Inch (12.7 mm) Diameter, 0.250 Inch (6.4 mm) Maximum Recovered Inside Diameter, 6 Inch Lengths, 4 pieces, Black. Flexible tubing with an adhesive inner wall which seals and protects components from moisture and corrosion. Material Type is Polyolefin Cross-Linked with adhesive, Shrink Ratio is 2 to 1. Temperature Range is -67 degrees Fahrenheit to 230 degrees Fahrenheit (-55 degrees Celsius to 110 degrees Celsius). Flammability is Outer wall flame retardant, Voltage Rating is 600 Volts, UL Recognized, Military Specification is AMS-DTL-23053/4 Class 2 (material performance only).