The OBS Cube Mini Kit has two coil variations. The S1 coil is a mesh formed, 0.6ohm coil which is intended for lower nicotine strength e-liquid and a mouth to lung inhale. The N1 is a common style coil with a 1.2ohm resistance and is intended for use with higher nicotine strength e-liquid or Nicotine Salt E-Liquids and is for a direct to lung more or a cigarette style inhale.