Let’s clarify this post up since it’s looking like people misinterpreted my initial intention. As far as “knockoff”...no this isn’t a replica that someone copied the MZ65 dimensions, header length, diameter etc. It’s rather a similar looking expansion style chamber pipe that gives your MB an exhaust that looks kind of like a production dirt bike. That’s the reason I bought mine...not for a dramatic increase in performance. Now some here will argue that MZ65 this or MZ65 that...double the power, runs cooler, ideal stinger length yada yada. I could actually care less personally. I didn’t build an MB with the intention of taking a $139 motor kit and spending twice that amount buying pipes, boost bottles, reed cages etc to wring out another 2-3 hp. And I’m sure there’s others here that for the most part build them as a sidekick fun hobby, not an all out racing, how much power can I squeeze out of a mass produced cast China engine. So perhaps my title was worded improperly....it’s a good looking pipe versus some of the other choices out there that look hideous for a relatively affordable price. If you think it’ll make a difference either in looks or performance, stick to the tried & proven pipes out there. I decided to try it for $59....I’ve wasted money on worse things in my life, lol.