The JUSTFOG Q16 Pro Starter Kit is a pro version of JUSTFOG Q16 Kit. With 900mAh inbuilt battery, the JUSTFOG Q16 Pro provides an all-day-long vape to starters. The easy top refill ensure an anti-leak vape too. The JUSTFOG Q16 Pro has a 4-level voltage adjustment from 3.5V to 4.4V, meeting your different vaping needs. The constant voltage output of JUSTFOG Q16 Pro brings a stable performance to the users.