Extruded polythylene foam 1.Anti-collision and heat insulation 2.Smooth Surface 3. ... .no toxic.durable in water ,could filter air,dustExtruded polythylene foam could stand some press ,closed cell .,10-60ppi ,good elasticiry ... .durable in water ,could filter air,dust.1 .pu foam material2, reticulated, mesh,10ppi-60ppi,3 good resilient, good air permeability (95 ...