When heated, the cleaners break down to include Phosgene gas which is fatal in small doses. For Chinese Diesel Heater Exhaust Pipe - 23mm I.D. Flexible Waste Heat Extractor Fins. Note: In a few of the images, the T-bolt exhaust clamp can also be used to secure one end of the heat extractor fins, thus, covering more of the exhaust pipe at the exhaust port.
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