This is a bracket for Viair 91028 2.5 Gallon Air Tank (Six 1/4" NPT Ports, 200 PSI Rated) to mount it in 2019-2026 Ram 3500 DRW trucks with factory bed. It may also work for 2010-2018, and it may also work for SRW trucks, but I have not yet had an opportunity to test-fit these trucks.
 
This bracket is made out of 1/8" P&O steel, laser cut and CNC formed. It ships bare steel. It also includes the hardware to mount to the truck and hardware to mount the tank to the bracket.
 
Air tank available here: https://amzn.to/4gPBYnD