Six foot section of Armaflex closed-cell foam pipe insulation for 1" iron pipe or 1-1/4" copper pipe, with 1/2" wall thickness. Sections are spilt lengthwise and is rated -30°F to 200°F. Armaflex lightweight closed-cell rubber pipe insulation is ideal for liquid pipe lines, acting as a barrier to protect against both heat loss and condensation. If the foam pipe insulation is exposed to outdoor elements, it is necessary wrap it in a weather resistant coating. To determine the measurements of the insulation, measure the outside diameter of your pipe and then reference the chart below. Please note that there is always a small margin of allowance with pipe sizing.