Construction These unique up pipes are constructed of 2 mandrel - bent 304 stainless steel tubing with a .120 wall for strength and durability. 2 Inner Liner Flex Pipes The up - pipes utilizes heavy duty 2 flex tubes with internal inner liner. Leak - Free Seal High quality 38 thick flanges are used for a complete 360 degree sealing surface. Note This is a Race Only product used s olely for competition. Its use is limited to closed - course and open - course racing that is formally sanctioned by a recognized racing organization. Any other use including recreational off - road use could be in violation of local, state and federal laws.