... .no toxic.durable in water ,could filter air,dustExtruded polythylene foam could stand some press ,closed cell .,10-60ppi ,good ... toxic.durable in water ,could filter air,dust.1 .pu foam material2, reticulated, mesh,10ppi-60ppi,3 good resilient, good air ... in aquarium filter ,water filter ,air filter ,water pump,medical machine,cleaning kitch and dish ect. 6 UV- protection, environment , have passed ...