Dual-Coil system Standard Mode – Each coil will work individually (Increase the longevity of your device) Boost Mode – Enables both coils to work at once (Uses more juice for a stronger hit) Mode Change – The button next to the charging port can be pressed to alternate between the two modes. Press the button once and you’ll see the light change to orange. This means you’re in boost mode. Standard mode is shown by a white light. Digital display screen to show E-Liquid and battery levels. Vibration: One Vibration : Battery Lower Than 50% Two Vibrations : Battery Lower Than 30% Three Vibrations : E-Liquid Lower Than 50%