This is the 2007+ Chevy raised gas tank crossmember. It is designed to move the gas tank up and in to help with ground clearance and airbag clearance on our under rail 3 link kits. This gas tank crossmember helps make our 3 link wishbone installs go much smoother because they locate the front wishbone pivot point. 

Link to install : 07+ CHEVY 3 LINK KIT - NFAMUS GALLERY (smugmug.com)

Link to Under Rail 3 link Kits: https://www.nfamusmetal.com/07-chevy-under-rail-3-link-kit/