Safety is a top priority with the SH300-SH330B humidifier tank. Equipped with an automatic shut-off feature, this tank will turn off when the water level is low, preventing any potential hazards. This gives you peace of mind knowing that your humidifier is safe to use, even when you're not around to monitor it. https://www.ultragreenbattery.com/product/new-for-sh300-sh330-sh360-sh330b-humidifier-tank-set