The hay helps dry the calf.  The next version of the calf box will have a divider and possibly a fold down section in the doors so it can double as a dog box.

The floor is on ball bearing rollers.

Most nights the lamps will raise the temp inside the insulated box 15 degrees above outside temp in about 30 minutes. The calf's body heat will raise the temperature even more.

The expanded metal allows for easy clean up and permits moisture to get away.

The new easy tatch pin.