Comparisons

MTL, RDL and DTL compared

These abbreviations do not describe device quality; they describe airflow and inhalation style.

Editorial status: Aug 7, 202618+

MTL: tight and indirect

With MTL, aerosol is held in the mouth before inhalation. Tighter airflow, lower power and more modest liquid consumption are typical.

RDL: the middle ground

RDL is inhaled directly but retains noticeable draw resistance. The setting sits between tight MTL and very open DTL.

DTL: open and direct

DTL uses substantial airflow and is inhaled directly. These setups often use lower resistance and higher power, so coil, battery and liquid must be matched.

Note: This content is for general information and does not replace medical or legal advice.

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Related terms

Use & vaping styles

MTL (mouth to lung)

MTL means mouth to lung: aerosol is drawn into the mouth first and then inhaled into the lungs. It typically uses a tighter draw, higher resistance and lower power.

Open term

Use & vaping styles

RDL (restricted direct lung)

RDL sits between MTL and open DTL. The draw goes directly to the lungs but remains noticeably more restricted because airflow is limited.

Open term

Use & vaping styles

DTL (direct to lung)

DTL means direct to lung: aerosol is inhaled directly in an open draw. It commonly uses airier atomizers, lower resistance and higher power.

Open term

Parts & technology

Airflow is the movement of air from the inlet across the coil to the mouthpiece. Its volume, direction and speed cool the heater, carry aerosol and determine draw resistance, interacting with power and chamber design.

Open term

Use & vaping styles

Sub-ohm vaping

Sub-ohm describes vaping with coil resistance below 1 ohm. These systems often use higher power and greater airflow and liquid flow; device, battery and coil must be designed for it.

Open term