Hi, According to the previous owner, it is a NOS 1960's British made, upswept. I had the same one on my SR500, which I bought on Ebay- So I just had to buy this 2010 G5 Deluxe. It is a 2 piece assembly with a bolt in shower drain type baffle. It's fairly quiet when idling, but barks some on acceleration. Bike runs well & strong with it. Ah, sounds of my youth. Cops here don't mind, but I never crack it on when they are watching. See Photo.