Pipe Fitting Insulation Tee Wall Thickness 2 In. Material Fiberglass Insulation Nominal I.D. 1-3/8 In. Color White For Tube I.D. 1-1/4 In. For Tube O.D. 1-3/8 In. Temp Range 0 Degrees to 450 Degrees F Approx ''R'' Factor 10 For Use On Piping Standards ASTM C547 ASTM C408