It is a kerker, not sure if its a K3. Is that good? I don't know anything about exhaust. I assumed it was just a piece of junk.
If it's in good shape it's not junk, those were around in the mid 80's and quality was pretty good, if it's in good shape you may want to keep it, wrap the affle if it's too loud though. If you want to let it go cheap PM me.
Here's one on a GPZ550.[youtube=425,350]<object width="425" height="344"><param name="movie" value="
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