Here's a look at the Axis RC Chassis Brace for the Traxxas Slash 4x4, LCG and Rally. This machined aluminum and carbon fiber brace strengthens the chassis by being mounted between the shock towers. At 1.8 ounces, it also keeps the stock plastic shock towers from flexing to add a truer suspension feel with out adding too much weight. To top it off, it's made in USA!
Here's where I got it and some info from Axis RC:
This innovative brace connects the front and rear shock towers to stiffen the body mounts and chassis. This prolongs the life of the body and the drivetrain. Constructed of billet aluminum and carbon fiber, this brace is strong and light. Included in the kit is the brace, hardware, and body saver block along with complete installation instructions. USA MADE.