Durable Material: Rear shock crossmember made from heavy gauge steel, surface is galvanized, which is more anti-rust and better welding effect. Fitment: The crossmember fit for 1999-2006 Chevy Silverado and GMC Sierra 1500 and 2500, Non-HD. Easy to install: No need to remove the truck bed, just remove the old shock. Set the replacement cross member in place, weld it solid, and reinstall your fuel tank and new shocks. Function: Tank Support Crossmember Replace for the Crossmember Located Forward of the Rear Axle that Supports the Rear End of the Gas Tank. Make you safer on the road. Design: Shock Mount Crossmember is a hollow tube that runs from side to side on the frame and supports the upper left side shock. Two outer end plates and right side inside mount plate are sent loose for ease of installation.