Caddellite Helm
This helm is made of the rare metal Caddellite. It protects like a Great Helm, but additionally has the ability to filter out any kind of hurtful noise, protecting the ears of the wearer.
When trying to enter the Cube Generator in Ultima VII, the party had to flee from a high-pitched, destructive noise. After some consulting, they retrieved Caddellite from Ambrosia and asked Zorn in Minoc to make them helmets from the metal. With the helmets it was easy to breach the defense of the Generator.