Pibow case for the HiFiBerry DAC

This is a Pibow case that has been extended by additional layers to house a Raspberry Pi with the [HiFiBerry DAC](http://www.hifiberry.com/dac "HiFiBerry DAC").
You can use the bottom and top layer and layers 1-4 of the original Pibow case and just print the new layers or simply create all layers.
The drills have a diameter of 3mm.