Since, in my view, Chinese Mah Jongg sets seldom came with racks, western manufacturers filled the void.
The majority of the racks in my collection were made in America or Europe. They regularly come in their own box and often feature explicitly name and logo of the supplier, frequently a manufacturer of Mah Jongg sets.
Racks can be very simple. But there are skilfully finished specimens too. Many, mainly western sets have racks made of wood, tin or cardboard, integrated in their boxes.