... insulation tube and sheet is composed of Ethylene-Propylene-non-conjugatedDieneRubber, It is a kind of nonpolar , Saturation and no cracks rubber ... cell foam structure,water absorption rate is low(The wall thickness of closed cell foam is 4 micron. closed cell foaming capacity ... ,20mm,25mm,30mm,50mmwidth:1m,1.2m 10mm and 50mm thickness EPDM rubber insulation sheets