Hi Kam,

It's actually called Quiet Steel and it is manufactured by Material Sciences Corporation Engineered Materials and Solutions Group. Lifted from a different website: Quiet Steel is a laminate of (1) a layer of steel (usually 0.5 to 1.5 mm) (2) a viscoelastic layer (about 0.001 “ of an engineered plastic which can be conductive for spot or stud welding) and (3) another layer of steel, same thickness as the first layer.


http://www.quietsteel.com/quietsteel.html