3M lead foil tape 420, linered tape used as a maskant in electroplating and as a moisture and radiation barrier in certain applications. Lead foil backing provides good conformability having electrically and thermally conductive properties. This linered tape can be easily die-cut into special sizes or shapes. - 3M lead foil tape 420 is backed with a rubber adhesive, offering excellent conformability in a variety of application conditions, indoors and out. Best results are obtained when applied to a clean dry surface above 32 °F.