Pipe Insulation, Insulation Material Buna-N Rubber/PVC, Installation Style Unslit, Inside Diameter 4 1/8 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 5.4, Form Tube, For Copper Tube Size 4 1/8 in, For Pipe Size 3 1/2 in, Flame Spread Index 61, Smoke Developed Index 86, Foam Cell Type Closed, Plenum Rating Plenum Rated, Flexibility Flexible