To use the preheat function on the best cart pen, follow these steps:

1. Activate the Device: Ensure the best cart pen is charged and ready for use. The best cart pen comes with a built-in rechargeable battery and a USB Type-C charging port for convenience.

2. Locate the Firing Button: The best cart pen features a user-friendly firing button. This button is used to activate the preheat function as well as to take puffs.

3. Engage the Preheat Function: To activate the preheat function, press the firing button multiple times (usually 2-3 times quickly). This will initiate the preheating process, which warms up the device and ensures a smooth vaping experience.

4. Wait for the Indicator: Some best cart pen may have an LED indicator that lights up during the preheating process. Wait until the indicator shows that the device is ready (usually indicated by a change in color or a steady light).

5. Start Vaping: Once the preheat function is complete, you can start vaping by pressing and holding the firing button while inhaling.

Using the preheat function helps enhance flavor and vapor production, making your vaping experience more enjoyable. If you have any further questions about the device, feel free to ask!