Underseat storage question on CrewMax-odd findings on my truck

It appears I have some boxes already installed that may be part of a subwoofer box? I’m not clear on what these are but, maybe someone has a similar set up. It appears to be part of the sub box behind the seat to add air volume.

 

Never seen that before. Maybe theres drugs in there.

 

Are they connected to sub box?

If not drugs, a pile of money!

 

Yes connected to the sub box. Seems like a crazy custom enclosure. I tried to pick one up or pull it from the square cut out area and realized it’s mounted. Then I tried to find a break and realized it had been made part of the box!

 

I’ll probably pull the passenger side rear seat and confirm but, it seems pretty clearly to be one piece.

 

looks like the sub boxes I had in my El Camino. For volume the L went into that space behind the seat. For this application it goes under the seat.

 

https://www.onlinecarstereo.com/Car...MIt6_lu9jm4QIV2brACh3niwHMEAQYAiABEgIGRfD_BwE

 

Extra custom! Some extra work on design, construction, and mounting for sure.

There are sub boxes available for behind seat only....