Kundel trench boxes are designed to last. This is thanks to the superior engineering and the fact we use no foam fillers nor wood. There is no risk of checkerboard occurring with these steel boxes. Hence, trench box re-certification is a common occurrence.
Contractors, developers, and anyone who buys these types of capital investments understand they may cost a lot and wish to get as much life from their investment as possible.
If you need your Kundel box re-certified; just send in clear pics of the box. No need to ship somewhere and have it shipped back to you.