Is used for sealing heating and cooling - like duct tape used to be but this material is superior for sealing heating/cooling ducts. I get mine from a big, local HVAC contractor instead of Lowe's. Price is a bit better.

Another good one is the same foam without the aluminum backing used for wrapping pipes. In the plumbing section.

Chris M.
'78 corvair powered westy

A trade name or usual application of this product would be helpful.  In some
of these big box stores, a customer can know more about the stock than a clerk
does.