Original K-rations are expensive, especially if you want a full set of three boxes. Good quality reproductions are widely available, but on display with original ration items, they don’t look quite as good anymore. Here’s how to ‘age’ your repro boxes. It’s so easy you can’t screw it up. Just wet your hands with olive oil and rub the boxes. Start with the inner cartons to practice. You will want to use more olive oil on the inner cartons, but start with a little and then add more when you get the hang of it. Then all you need to do is knock the corners of the boxes about on a hard surface and scratch the edges of the outer box with your fingernails to give them that used look.

Late war K-rations that received the same treatment.

This is what the carboard looks like before treatment

And after rubbing it in with olive oil. The inner boxes should be darker, so they have to be pretty much saturated with oil.

Details of the 'aging'