Ferrets need a spacious cage that allows them to move around comfortably. The cage should have multiple levels or platforms for them to climb and explore. Additionally, ferrets need bedding material such as blankets, towels, or hammocks for warmth and comfort. They also require food and water dishes, chew toys, a litter box, and a hiding place or shelter within the cage. It's important to regularly clean and maintain the cage to ensure a healthy environment for your ferret.