Pipe Insulation Insulation Material Buna-N Rubber/PVC Installation Style Unslit Inside Diameter 4 1/2 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 4.4 Form Tube For Copper Tube Size Not Applicable For Pipe Size 4 in Flame Spread Index 46 Smoke Developed Index 71 Foam Cell Type Closed Plenum Rating Plenum Rated Flexibility Flexible This product contains a chemical that is regulated under California Proposition 65. Warning: This product contains a chemical known to the State of California to cause birth defects or other reproductive harm. -