Polyethylene foam, unlike reticulated polyurethane, is a close cell material. This very lightweight, cost effective foam is extremely durable and shock absorbent.  Ideal for packaging, polyethylene foam is resilient, strong, and can dampen the effects of vibration.  Polyethylene foam also encompasses insulation properties and has a high resistance to chemicals and moisture.  Buoyancy is another feature of polyethylene foam that makes it ideal for floatation equipment.