Arrow 71735PK Race-Tech Titanium Slip-On Mufflers w/Carbon End Cap for Yamaha YZF R1 09-14Arrow Pair Exhausts Race Tech Race Tech exhaust range was the first series of silencers designed with the new diamond shaped section. This design replaced (quite completely, but not at all) in the past years the older silencers sections, oval and cylindrical. The advanced profile (looks like a diamond, with smooth corners) makes it possible to reduce dimensions with respect to an exhaust with a more traditional shape and with an equivalent section