Fill with 2 Boveda 49% RH for an Acoustic Guitar | Fretted or Bowed Instrument | Woodwind

Double Boveda Fabric Holder


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The ultimate versatility to control moisture for a wood instrument!

  • Perfectly preserves humidity in the body of your acoustic guitar
  • Lays across the strings of the instrument to efficiently humidify the entire guitar or instrument case
  • Conveniently snugs around the tuning pegs of a cello or concert bass or under its tailpiece

Struggle to maintain proper RH (relative humidity) in an instrument case? Compensate for extreme conditions, use an additional fabric holder in your case if you live year round at:

  • High humidity
  • Low humidity
  • High elevation
This Double Fabric Holder is designed for:
  • 2 Boveda 49% RH Standard (sold separately here) OR Boveda 49% RH High-Absorbency Size 40 (sold separately here)
  • A semi-hollow body, archtop, electric or acoustic guitar
  • A large bowed instrument
  • A large fretted instrument
  • A harp
  • A large woodwind



  1. Just insert an unwrapped Boveda 49% RH into each pouch of this protective fabric holder.
  2. Place in the case anywhere that allows for airflow and prevents puncture when you close the case:
    - Drape over the strings and into the sound hole
    - Under the neck, headstock or tailpiece
    - Across the strings or entire instrument
    - Around tuning pegs
    - Into a hollow of the case
  3. Close the case's lid. Always keep your case closed when using Boveda.

Always insert Boveda into a pouch of a Boveda fabric holder before placing in an instrument case. The fabric holder allows Boveda to last longer and work better and acts as a liquid barrier if a packet is accidentally punctured. 

Do not mix different Boveda RH levels within the same instrument case. And do not use Boveda in the same case with other humidification products because they will fight against each other and reduce the efficiency of Boveda.

Fill with EITHER:
- Two (2) Boveda 49% RH Standard for wood instruments (Packs are not included, but available separately here.)
- Two (2) Boveda High-Absorbency 49% RH Size 40 for wooden instruments in high-humidity climates. (Packs are not included, but are available separately here.)

Boveda will last 2-6 months depending on the time of year, your climate and your case.
Unopened package: Up to two (2) years

Do the touch test. Order replacement packs BEFORE Boveda is totally rigid to avoid a lapse in humidity protection for your instrument.
Boveda is still working if you feel:
• Hardening at its corners
• Soft spots among some hard areas
Boveda is expired if:
• The entire pack feels rock solid all the way through. 

Achieves and maintains a constant relative humidity (RH) range between 45% and 55%.

Food-grade salt, purified water and a food-grade thickening agent sealed inside a leakproof membrane. 

Folded: 6.625"/16.83 cm x 4.25"/10.8 cm
Unfolded: 12.5"/13.75 cm x 4.25"/10.8 cm