Mainstays 0.31 Gallon Ultrasonic Cool Mist Humidifier with Aroma and Nightlight, Black
Mainstays 0.31 Gallon Ultrasonic Cool Mist Humidifier with Aroma and Nightlight, Black
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Mainstays

Mainstays 0.31 Gallon Ultrasonic Cool Mist Humidifier with Aroma and Nightlight, Black

909 ratings
Mainstays 0.31 Gallon Ultrasonic Cool Mist Humidifier with Aroma and Nightlight, BlackMainstays 0 31 Gallon Ultrasonic Cool Mist Humidifier with Aroma and Nightlight Black
Actual ColorBlack

Key item features

  • Ample Coverage: Features a 0.31-gallon water tank, capable of efficiently humidifying personal residential spaces covering up to 219 square feet.
  • Extended Operation: Delivers up to 15 hours of cool mist on its low setting; actual runtime can vary depending on home humidity and water temperature.
  • Compact Dimensions: Boasts a compact design, measuring 6.14 x 6.14 x 7.8 inches and weighing just 1.32 pounds for easy placement in various personal areas.
  • Quiet Safety: Operates at a quiet 35 dB, ensuring minimal disturbance, and incorporates an automatic shut-off feature for safe, unattended use.
  • Multifunction Features: Includes convenient built-in aroma diffusion and a soft nightlight, providing additional comfort and ambiance in residential settings.
  • Standard Power: Powered by a corded electric connection at 120 V, this humidifier is designed for consistent and reliable residential operation.
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Specs

Humidification method, UltrasonicCoverage area, 219 sq ftRun time, 15 hVolume capacity, 0.31 galDispensing temperature, Cool MistBrand, Mainstays

About this item

Product details

This Mainstays ultrasonic cool mist humidifier is a compact way to add moisture to the air in personal residential spaces. It covers up to 219 sq ft, giving you a concrete figure to compare against the room or corner where you plan to use it. Measuring 6.14 in x 6.14 in x 7.8 in and weighing just 1.32 lb, it has a small, lightweight footprint that fits easily on a countertop, desk, or bedside table. The 0.31 gal tank runs up to 15 hours on the low setting; that runtime is based on using cool water and the low mist level, and actual runtime may vary based on your home's natural humidity, the water temperature, and the mist setting you choose. Beyond basic humidification, it also includes built-in aroma and nightlight features.
  • 0.31 gal water tank capacity
  • Covers up to 219 sq ft for room-size comparison
  • Runs up to 15 hours on the low setting; runtime is based on using cool water and the low mist level, and actual runtime may vary based on your home's natural humidity, the water temperature, and the mist setting you choose
  • Assembled dimensions of 6.14 in x 6.14 in x 7.8 in; weighs 1.32 lb for easy placement
  • Operates at 35 dB; corded electric power at 120 V
  • Includes automatic shut-off
  • Includes aroma and nightlight features
  • Intended for residential use
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Specifications

Humidification method

Ultrasonic

Coverage area

219 sq ft

Run time

15 h

Volume capacity

0.31 gal

Customer ratings & reviews

4.3 out of 5 stars
stars
909 ratings208 reviews
Includes global ratings and reviews
How item rating is calculated
  1. 5 stars71% (647)
  2. 4 stars12% (110)
  3. 3 stars5% (47)
  4. 2 stars3% (31)
  5. 1 star8% (74)

Reviews summary

Pros

  • : The unit fits well on end tables and in small rooms.
  • : Simple operation makes it easy to use.
  • : The unit fits well in one- and two-room apartments.
  • : Offers good performance at a reasonable price.
  • : Filling process is straightforward.
  • : The unit provides three brightness levels and can be switched off.
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Showing 1-3 of 208 reviews

Oct 29, 2026
Reviewer name: Danielle
Item details
Color: Blue
5 out of 5 stars
5 out of 5 stars review

Verified Purchase

Small but effective in a small space.

This humidifier is smaller than I expected it to be, but what I found is it's perfect size to sit on a bedside table and you aim it right towards you so it doesn't humidifier a huge space but it will humidify quite well where you're sleeping or sitting and it works out perfect for me for those reasons. But honestly, if you're looking for something to do a sub substantially sized room, you really need something bigger than this..

Helpful?60C7GRWQQO2016546210464
Sep 29, 2026
Reviewer name: Evee
Top Reviewer
Item details
Color: Blue
5 out of 5 stars
5 out of 5 stars review

Verified Purchase

Tiny But Mighty Humidifier Has Nightlight!

Tiny but mighty ultrasonic cool mist humidifier. It is the perfect size for my home office. It is so quiet and puts out plenty of humidity. You can add essential oils to the included little pads that you put into the little hatch on the outside of the unit but I haven't tried them yet. It has a nightlight which comes in handy.

Helpful?60C7GRWQQO2016546210464
Nov 8, 2026
Reviewer name: Pamela
Item details
Color: Black
5 out of 5 stars
5 out of 5 stars review

Verified Purchase

Great Humidifier for House Plants

I bought this to add humidity to my plants. I wanted an inexpensive, small one that would blend in. This works well for my needs. it's very lightweight and the mist fills the air right away. I've used high quality Honeywell humidifiers in the past for healthcare, but this one is perfect for my tropical plants %26 ferns.

Helpful?60C7GRWQQO2016546210464
Current price is $17.84
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