With a distinctive sound as you shift through the gears, coupled with enhanced power and torque, all encapsulated in a full titanium system, the Slip-On Line (Titanium) offers the Akrapovic experience while meeting ECE type approval. Constructed from lightweight high-grade titanium alloys and finished with two sets of carbon-fibre / titanium tailpipes, the system features complex parts crafted at the in-house titanium foundry, including the housing of the valves and collectors from the central muffler to the tailpipes. Two valves one on each side of the muffler tailor the gas flow to help produce that unmistakable Akrapovic sound, which is distinctly different from the X5M with a stock system. The exhaust tone is most noticeable as you move through the gears and accelerate, and this can be further controlled through the addition of the optional Akrapovic Sound Kit to provide increased aural pleasure. Akrapovic has achieved power gains of 12.1 hp at 2,400 rpm and torque increases of 35.4 Nm at 2,400 rpm when tested on the Akrapovic dyno against a BMW X5M with a stock M Sport exhaust system for comparison. As a further enhancement, Akrapovic has created optional parts to change the visual appeal of the car and accompany the beautiful finish of the systems tailpipes. With a handmade carbon-fibre diffuser, an added special touch can be made to the visual experience.With the installation of Akrapovic Sound Kit, ECE type approval for the Slip-On Line (Titanium) exhaust system is not valid.For non-OPF vehicles, the ECE type approval certificate is not valid.For installing the slip-on system, the stock exhaust system has to be cut. Please read the instructions carefully before the start of the installation.