GM Accessories Silverado/Sierra Crew Cab Underseat Storage - $120 (Dayton)

Brand new GM OEM part: 23183674 for 2016-2018 models.
General Motors GM Accessories Crew Cab Underseat Storage Compartment in Black Contain, organize, and conceal items under the seat of your vehicle with the GM Accessories Underseat Storage Organizer.
It turns unused space into valuable storage for such items as tools, sports gear, extra jacket and more.
See image for models covered.