When I as looking at the different options it seemed to come down to a choice between asphalt based and rubber based versions. In my mind I pictured my car sitting in the sun on a hot summer day with the windows rolled up and I imagined what kind of out gassing would be going on and how it was going to smell when I opened the door to climb in. I went with the rubber over the asphalt. Basically the same stuff though. Mine is made for wrapping HVAC vents.