First, make sure the air flow control is open on the tank. Second, the K1 Stealth uses the BVC coils which are for mouth to lung (MTL) vaping only, NOT direct to lung (DTL). For MTL vaping the device will not give you huge clouds.
Hi friend, the K1 stealth is a very strict MTL kit mainly for the nicotine users, if you'd like big vapor or more airflow, we would suggest you trying some DTL or light DTL devices.
charlzrocks
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