ZEUS Grinders are known for their exceptionally high quality. These Grinders are made of Aircraft Grade Anodized Aluminum (AGAA). Anodized aluminum is strengthened to resist tuff environmental pressure. This material can be nearly as hard as diamond under the right anodizing process. Many modern buildings use anodized aluminum in places where the metal framework is exposed to the elements. Anodized aluminum is also a popular material for making airplane and space craft components.