Final answer:
The keys to Category III and IV AA&E can be secured in steel containers that are at least 12-gauge or its equivalent. Steel cylindrical containers and high-density polyethylene cylindrical containers are suitable options for securing the keys.
Step-by-step explanation:
The keys to Category III and IV AA&E (Arms, Ammunition, and Explosives) can be secured in steel containers that are at least 12-gauge or its equivalent. The use of steel containers ensures that the keys are stored securely and protected from external threats.
For example, one option for securing the keys could be a steel cylindrical container, which provides durability, strength, and resistance to tampering. Another possible option is a high-density polyethylene cylindrical container, which is lightweight, corrosion-resistant, and can also provide adequate security.
It is important to choose containers that meet the necessary security requirements and regulations for storing and securing highly sensitive materials such as Category III and IV AA&E keys.