Field Controls RC Series. I like the version that comes with a tee, black to match my pipe. Sometimes it is hard to fit it into a standard tee -- very tight fit -- but I have always been able to manage it. Lots of places to order it from, just ask Google. Shop around, you may be able to do better on price. This one is 6-inch, make sure you order the right diameter if the Chubby uses different pipe.
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