Ultem (PEI) is an amber transparent high performance polymer, which combines high strength and rigidity at elevated temperatures with long-term heat resistance. Ultem offers excellent dimensional stability combined with broad chemical resistance. Ultem is also inherently flame resistant and low smoke generating. It also offers excellent dimensional stability, excellent electrical insulating properties, and excels in medical reusable applications that require repeated sterilization. With a special order, you can purchase it in FDA compliant colors. Ultem 1000 excels in hot air and water environments. It's hydrolytically stable and retains 85% of tensile strength after 10,000 hour boiling water immersion and 100% of tensile strength after 2,000 steam autoclave cycles at 270 degrees F. It is also resistant to UV and gamma radiation.