High Density Polyurethane

Density: High Density means polyurethane foam which has expanded within a (usually rubber but sometimes metal) mold... (cont.)
 

Flexible Moldings

The foam, rather than hardening into a dense and rigid material, remains soft and flexible, thus allowing the moldings to follow the contours of your project... (cont.)
 

GRG

Density: Very dense. Composition of plaster and fiberglass. Surface Properties: Smooth or textured available. Moisture Resistance... (cont.)
 

PVC

Density: Very similar to wood. Surface Properties: Closed cell, transmits no water or water vapor. Smooth to lightly textured surface. Moisture Resistance: Excellent... (cont.)