google "fim isolation"
GalenCarol audio is really helpful and has a chart describing the effects of different isolation products
http://www.gcaudio.com/cgi-bin/store/showProduct.cgi?id=326
http://www.gcaudio.com/cgi-bin/store/showProduct.cgi?id=325
http://www.fimpression.com/SearchResult.aspx?CategoryID=3
GalenCarol audio is really helpful and has a chart describing the effects of different isolation products
http://www.gcaudio.com/cgi-bin/store/showProduct.cgi?id=326
http://www.gcaudio.com/cgi-bin/store/showProduct.cgi?id=325
http://www.fimpression.com/SearchResult.aspx?CategoryID=3