Pipe Insulation Insulation Material Buna-N Rubber/PVC Installation Style Unslit Inside Diameter 1 5/8 in Wall Thickness 1 in Overall Length 6 ft Minimum Operating Temperature -297 Degrees F Maximum Operating Temperature 220 Degrees F Facing Material Unfaced Color Black R Value 6.6 Form Tube For Copper Tube Size 1 5/8 in For Pipe Size 1 1/4 in Flame Spread Index 52 Smoke Developed Index 77 Foam Cell Type Closed Plenum Rating Plenum Rated Flexibility Flexible