The Yocan UNI has an adjustable width and height for the oil atomizers. As for How to use Yocan UNI, it's basic vaping 101 question.

Turn on/off
Click 5X in 2 Seconds to Lock/Unlock

Change Voltage
Click 3X to Change Voltage Setting

Preheat
Click 2X to Start 10 Second Preheat Cycle


yocan uni instructions

• Screw your cartridge onto the magnetic adapter and then place it into the cartridge chamber.
• Use the knob to adjust the shutter until it holds the cartridge firmly in place.
• (Optional) Use the lever to adjust the cartridge to the height you find most comfortable.
• Press the power button five times to turn on the device.

Or you can refer to this thread Yocan UNI Manual, to explore more vaping trick&tips