Are these to recess the subwoofer? Why would you want to recess your sub? If that is in fact what they are for, how does that effect the overall construction of your box? I am going to blueprint a new box for my trunk tonight hopefully.

 

Their rings are CNC cut rings specifically designed to hold thier woofers. They will actually make you anything you need ring wise for a cost.

 

what is their purpose? Cosmetic? Construction?

 

How do they recess the sub? Cut a wood ring and screw/glue it in?