Dynamat Dynaliner 12mm 1/2" Insulator Sound Proofing Mat Acoustic Foam DYN11103Dynaliner 1 2" Part Number: 11103 1 2" thickness best for Under Trim (Doors) and Fiberglass Enclosures. Dynaliner is the most effective automotive lightweight thermal insulator available, and perfect to use on top of Dynamat Xtreme. It is a soft, self adhesive closed cell rubber with thousands of cells packed extremely close together, which gives the material near zero air infiltration occurrences. This is the key to its ability to reduce heat, as