I needed something sturdy to take fish food from tank to tank. This design is made for the Xtreme Aquatic Food Jars that have a diameter of 66mm.

This is able to hold 5 jars, with an optional 6th where the logo is. They are a lose fit, if you wanted them to have a firm fit you would need to reduce the model size.

Extreme Fish Food Tray - 66mm Jars