I've not used one either but how does it cool if one ends sucking hot air past the filter n the bulb??
Am pretty sure you needing one for air to pass the cooltube n one for the stale air
Carbo filtter--------ducting------rvk------ducting--- smell n stale air gone
Fresh air---ducting----cooltube-----ducting------rvk-----heat from bulb gone
Am 99% sure that's how it works buddy but could well be wrong lol as usual
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