Slant Fin Humidifier - Warm Mist Germ-Free (3.5 gallon)

Slant Fin Humidifier - Warm Mist Germ-Free (3.5 gallon)

Slant Fin GF-350 germ-free warm mist room humidifiers for the home, bedroom, apartment or office use the germicidal power of ultraviolet light and vaporization for a 100% germ free mist for allergy, asthma and sinus sufferers. Warm mist humidifier ratings, reviews and comparisons. Reports on slant fin humidifiers by consumer experts.
These 3.5 gallon warm mist humidifiers feel like the warmth of a greenhouse, and will humidify a room exceptionally fast. An occasional gurgling sound may irritate some, but otherwise this is the quietest humidifier we carry. An ultraviolet light and vaporization assure a 100% bacteria free mist. Slant fin humidifiers do not have a digital humidistat, and mineral pads do need replacing if distilled water is not used. That being said, the Slant Fin is our favorite humidifier overall and its reliability record is excellent.

Slant-Fin Warm Mist Air Humidifiers - are ideal for someone who...

  • Suffers from allergies, asthma or sinus pressure and wants a portable warm mist air humidifier free of all common household bacteria, mold and spores that can breed in tap water
  • Wants a quiet, powerful air humidifier that uses both ultra-violet light and vaporization (boiling) to ensure a 100% germ free warm mist
  • Wants to prevent the creation of white mineral dust and scale buildup on the humidifier tank
  • Wants a warm mist air humidifier that can help save on energy bills
  • Wants easy-to-change water reservoirs that will last over 48 hours (GF-350 - 3.5 gallon model) without a refill
  • Needs to disperse humidity over 400 square feet of space (standard one room area)
  • Wants no replacement filters, wicks or cartridges
  • Wants a built-in medicine cap

Learn More about Humidifiers

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Cool Mist and Warm Mist Humidifiers Features Comparison

Features of the Slant-Fin Warm Mist Air Humidifiers - GF 350

  • Comfortable warm mist humidification utilizing both UV light and vaporization that is virtually 100% free of bacteria, mold and spores (proven in independent laboratory testing)
  • Quiet fan operation is ideal for bedroom use
  • Fan assisted warm mist delivery
  • Two water reservoirs with a total of 3.5 gal. capacity for 2-3 day operation
  • Humidistat with low to high output settings
  • Special disposable mineral pads absorb minerals and white dust which has been linked to certain health risks
  • Humidifies for 48 hours continuously (GF-350 model) on high setting without a refill
  • Tank has a large opening for quick and easy filling and a conventient lift out handle
  • Manual reset button
  • Lift-out tank with built-in handle and large refill opening
  • Built in medicine cup permits optional blending of respiratory medications
  • Absolutely no white dust is dispersed. Minerals do not go into the room air where you could breathe them in.
  • No replacement filters, wicks or cartridges
  • Replacement ultra violet bulb indicator light
  • 3-year limited warranty

Maintenance: The tank should be cleaned with a solution of mild detergent and water at least once a week during use. Rinse well. Mineral pads should be changed when they become hard. Two mineral pads are included installed, and one comes seperate. The mineral pads will absorb any minerals from the mist.The mineral absorption pad should be changed after approximately (3) weeks of continuous use, sooner if you have hard water. The ultraviolet light should be changed every 1-2 years.
Technical Specifications of the Slant-Fin Warm Mist Air Humidifier

Slant-Fin Humidifier Models

Slant-Fin GF-350 Humidifier

Type of humidifier mist

Warm Mist

Room area coverage

400 square feet

Water capacity

3.5 gallons



Unit Weight (empty)

9 lbs 7 oz.

Humidifier dimensions

14.25" H x 13.25" W x 14" L

UV Bulb life

2200 hrs or 1-2 years (depending on usage)

Refilling duration

2 days

Auto shut-off


Replacement UV bulb indicator light


Built-in medicine cup


Manual refill/reset button


Recommended cleaning period (unit in use)

Once a week

Humidifier Warranty

3-year limited

Reports by consumer experts on Slant-Fin Humidifiers
Courtesy of Allergy Buyers

The Slant-Fin GF-350 warm-mist air humidifier is truly unique from most other brands since they use an exclusive dual-germicidal process that includes ultraviolet light (UV) and vaporization (boiling) to deliver mist that has been laboratory tested to be 99.999% germ-free.

  • This humidifier clearly is ideal for those who are concerned about killing germs and bacteria
  • The mineral pads included with the unit do absorb minerals and white dust that often is emitted into the air with other warm mist humidifiers
  • A quiet humidifier - ideal for the bedroom
  • Stainless steel reservoir makes it quite durable
  • Lasts for 48 hours before refilling water


  • The unit still needs to be cleaned by hand at least once a week (although not as often as some other humidifier models we tested)
  • While there are no wicks or filters to change, the humidifier needs new mineral pads (3-4 weeks) and ultra violet bulb replacement every 1-2 years (see care instructions above).

Summary: The Slant-Fin GF-350 was rated excellent by our consumer staff and is the Allergy Buyers Club category winner for Humidifiers.

Slant Fin 3.5 Gallon Humidifier - Warm Mist


Availability: Will Ship in 3-4 business days.

Digital Thermometer and Hygrometer with Temperature and Relative Humidity Sensor


This thermometer indicates the temperature indoors or outdoors and the humidity indoors. It features a large digital LCD display with clock for easy reading, minimum - maximum temperature read out with memory, light button, wall mount or folding stand, 10 foot outdoor weather-proof sensor wire.

Slant Fin Humidifier Mineral Pads (pack of 6) and UV Replacement Bulb


Mineral Pads (pack of 6)- The Mineral Absorption Pads will play a major role in capturing and removing minerals from hot water reservoir, and preventing a stubborn mineral buildup. The mineral absorption pad should be changed after approximately (3) weeks of continuous use. If the water is "Hard Water", the pad should be changed more frequently. Comes with a replacement Ultra Violet Germicidal bulb for all Slant/Fin Humidifier models.