Pipe Insulation Insulation Material Buna-N Rubber/PVC Installation Style Unslit Inside Diameter 2 1/8 in Wall Thickness 3/4 in Overall Length 6 ft Minimum Operating Temperature -297 Degrees F Maximum Operating Temperature 220 Degrees F Jacket Material Unfaced Color Black R Value 4.5 Form Tube For Copper Tube Size 2 1/8 in For Pipe Size Not Applicable Flame Spread Index 38 Smoke Developed Index 63 Foam Cell Type Closed Plenum Rating Plenum Rated Flexibility Flexible