This is Shawnee in her Whelping box awaiting the arrival of her puppies. My husband made this out of wood and particel board. It is 4x6. The flooring is padded with foam matting and then lined with vinyl flooring for easy clean up. The sides are lined with 1x6 railings so that puppy can fit underneath to avoid being squashed by mamma.Since is winter we will attach a heating lamp above the box and a heating mat will be placed in the box for puppies to lay on. When they are first born they do not have the ability to regulate their temperature so you must keep their enviroment a balming 80 degrees.