About this 3D model

This is for mounting three boards -- such as the EC, relay, and extruder stepper driver boards -- to the side of a cupcake. It replaces my "Cupcake Gen3 Extruder Controller and Relay Board Mount" ( http://www.thingiverse.com/thing:6780 ), adding a mounting point for a fourth stepper driver for the extruder (or another board of comparable size, because it is fully parametric).