Pipe Fitting Insulation 90 Degrees Elbow Wall Thickness 1-1/2 In. Material Fiberglass Insulation Nominal I.D. 1-5/8 In. Color White For Tube I.D. 1-1/2 In. For Tube O.D. 1-5/8 In. Temp Range 0 Degrees to 450 Degrees F Approx ''R'' Factor 7.5 For Use On Piping Standards ASTM C547 ASTM C345