These are high output ported subwoofer flat packs made from a very good quality Carb 2 Compliant MDF. This is not the type of MDF that you will find at Home Depot or Lowes, it is highly refined MDF. Every panel is cut on a CNC machine with rabbet joints and dados to allow for easier and more accurate assembly. Rabbet joints and dados also give you a stronger enclosure because there's more surface area for the glue to bond to.
Click below for current models: