Which type of transfer container is a wooden tray covered in corrugated material?

The air tray is specifically designed as a transfer container consisting of a wooden tray that is typically covered with a corrugated material. This structure provides protection for the casket during transportation while keeping the weight manageable. The open-sided design of the air tray allows for ventilation, which can help to reduce odors during transit and assists with the preservation of the remains when transportation is necessary.

When comparing this with other options, the Ziegler case is generally a more enclosed and sturdier container used for transportation but does not have the same structure as an air tray. The wooden box, while it may be made of wood, does not specifically refer to the covered construction with corrugated material. The air pack is often associated with the concept of air cushioning but does not fit the description of a wooden tray. Therefore, the air tray distinctly meets the criteria outlined in the question, making it the correct choice.