CM-187B 7" Wrap Around - Custom Size per foot

An inexpensive tool for marking straight lines around
pipe, or for use as a straight edge. Made out of flexible
gasket material, with good resistance to heat and cold.
B (Black) material has a service temperature of up to 350°F. 

Formula -
5 x size of pipe 
divided by 12 = Length
Required in feet

Sold per foot