Smooth transitions in the mandrel - bent aluminum tubing decrease turbulence and minimize pressure loss, increasing horsepower and torque. This tube kit includes high - quality, stainless - steel, clamps and heavy - duty, 5 - ply, polyester reinforced silicone couplings for superior strength and durability. Finished in Wrinkle Black powder coating with a unique laser - etched aFe power logo for a custom look. When it comes to engineering for power, performance, protection and value, aFe POWER is the only choice.