2-way humidity control refills for starter kits

B49 Refills for Guitars & Other Wooden Instruments

Rated 4.7 out of 5 stars
28 Reviews
Starting at $19.99

Pack Quantity

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Replace your Boveda every (three) 3 months. Just slip these refills into the Boveda Leakproof Holder(s) and slide them back into your instrument case. Set up a subscription to get replacements auto-shipped to you, so there's no lapse in humidity protection for your wooden instrument.



Using Boveda to balance humidity in an instrument case:
  • Requires zero maintenance—no more filling messy hoses and snakes and wetting sponges
  • Maintains an ideal relative humidity range for instruments—40-60% RH
  • Prevents wide fluctuations in humidity that cause the wood to expand or shrink, and degrade its performance abilities


  • ALWAYS insert Boveda into a leakproof holder before using in your instrument case. The holder acts as a liquid barrier if a packet is accidentally punctured while extending the life of your Boveda packets. The patented interior material allows water vapor to pass through to your instrument. The exterior is soft, like a polishing cloth, so it doesn’t scratch the finish.
  • DO NOT mix different Boveda RH levels within the same instrument case. 
  • DO NOT use other humidification products with Boveda in the same case because they will fight against each other and reduce the efficiency of Boveda.

  1. Slip the Boveda pack into the pouch of its leakproof holder. (DO NOT OPEN the Boveda itself.)
  2. Place in the case anywhere that allows for airflow and prevents puncture when you close the case:
    - Under the neck or headstock
    - On the strings

    - Open area in the case
  3. Close the case's lid. Always keep your case closed when using Boveda.


  • 4-Pack: Packaged in a resealable high-barrier heavy-duty plastic bag with a zip closure. Each Boveda is not individually overwrapped. 
  • 20-Pack Brick: Packaged in a heavy-duty plastic bag that is resealable using its attached tape enclosure. Each Boveda is not individually overwrapped.

    Unopened, Boveda can last up to 2 years.


5.25"/13.34 cm x 3.5"/8.89 cm


Replace Boveda 2-way humidity packs every three (3) months.


Achieves and maintains a constant relative humidity (RH) range between 40% and 60%, the industry standard for wooden instruments.


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

Our Customers Say

Rated 4.7 out of 5 stars
Based on 28 reviews
Total 5 star reviews: 23 Total 4 star reviews: 2 Total 3 star reviews: 2 Total 2 star reviews: 1 Total 1 star reviews: 0
89%would recommend this product
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28 reviews
  • KD Profile picture for Kenneth D.
    Kenneth D.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5 stars
    11 months ago
    Conditioning Cases Prolongs Boveda Effectiveness

    Only 2nd purch of the 20-pack. I have a few acoustics. My Bovedas last about a year. I pre-conditioned all my cases and run humidifiers in the cold dry season.

    I also use Boveda for cannabis and my jug of Orville Redenbacker popcorn.

    D'Addario offers a two-way Boveda-based system. They do not offer, nor do they tell purchasers the necessity of Case Conditioning. Musicians who don't condition their cases complain that the Bovedas get hard in just a few weeks unlike mine which are lasting 52 weeks and most packs still not hardened (with only some hardening apparent.)

  • AM
    Armen M.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5 stars
    12 seconds ago
    Great product

    I live in North Central Arizona, the humidity changes every day. Sometimes it's low and others it's high. The Boveda refill helps keep my Fender Acoustisonic from warping the neck or cracking the body. Thanks for the opportunity to share this.

  • NR
    Nan R.
    Verified Buyer
    I recommend this product
    Rated 4 out of 5 stars
    6 days ago
    Excellent product

    Especially during winter when it gets so dry indoors. I’ll be sure to recommend this product to other fellow piccolo players. My only complaint was that I was automatically signed for auto ship which I don’t think I signed up for. Best to ask when ordering if that’s what we want.

  • SC
    Steven C.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5 stars
    1 month ago
    Boveda humidification systems

    Excellent product. We use them on all of our guitars and Ukuleles. They do an excellent job. I would highly recommend the product.

  • JK
    Jeff K.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5 stars
    1 month ago
    Works well

    These keep my guitar at the proper humidity. No maintenance. Best value for me.

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