Pipe Insulation Insulation Material Melamine Installation Style Hinged with Self-Sealing Flap Inside Diameter 1 3/8 in Wall Thickness 1 in Overall Length 4 ft Minimum Operating Temperature -40 Degrees F Maximum Operating Temperature 350 Degrees F Facing Material ASJ Facing Color White R Value 5.82 Form Tube For Copper Tube Size 1 3/8 in For Pipe Size Not Applicable Flame Spread Index 25 Smoke Developed Index 50 Foam Cell Type Open Plenum Rating Plenum Rated Flexibility Flexible