Solid polyurethane is an elastomeric material of exceptional physical properties including toughness, flexibility, and resistance to abrasion and temperature. Polyurethane has a broad hardness range from eraser soft to bowling ball hard.  Urethane combines the toughness of metal with the elasticity of rubber.  Parts made from urethane elastomers often outwear rubber, wood and metals 20 to 1. Other polyurethane characteristics include extremely high flex-life, high load-bearing capacity and outstanding resistance to weather, ozone, radiation, oil, gasoline and most solvents.