... closed cell tube and sheet insulation pipe is composed of Ethylene-Propylene-non-conjugatedDieneRubber, It is a kind of nonpolar , Saturation and no cracks rubber ... absorption rate is low(The wall thickness of closed cell foam is 4 micron. closed cell foaming capacity is above 95%,water absorption rate ... 60mm,76mmthickness:10mm,13mm,20mm,25mm,32mm,50mm EPDM flexible elastomeric thermal insulation tube