D'Addario Accessories Guitar Humidifier Packs - Two-Way Humidification System Conditioning Packets - For Maintaining Proper Guitar Humidification Level - 3 Maintain Replacement Packets

If you have a guitar, you need to keep it properly humidified. These packs are great and work like a charm. The only time they've failed to maintain the internal humidity in a guitar case to within +/- 1% of their labeled value was when I put them in a case that had a really bad air gap when closed...definitely not the fault of the pack, it was competing with the outside air and still managed to get the internal humidity to within 5% of the value. These refill packs last a while and are great if you have multiple guitars to humidify.

I’ve used these for the past 10 years! Never had an issue with them and they do a great job of keeping the wood of my guitar just right.They are very easy to use and for the money, I don’t think you can go wrong!Only thing I’d recommend is that you keep your guitar in a hard shell case when using these.

Maintained a humidity of 45-50% in my guitar case. Did exactly what I needed it to do-even in these cold and dry conditions

Anybody who has a nice acoustic guitar knows it's a delicate thing, made of natural wood. If you don't humidify that wood, it will crack, ruining the guitar or necessitating expensive repairs. The Daddario Humidifier Packs I've used are amazing, easy, and effective. They last about 6 months and AUTOMATICALLY keep your guitar (if stored inside its case) at an ideal 45% humidity level. Just put one of the 3 packs that come in the box under the headstock of your guitar; and hang the other two -- like a saddle on the back of a horse -- over the strings. That's it. I like this humidifying solution MUCH more than the 'sponge' or 'soundhole' humidifiers, which -- even when inserted properly -- stretch your strings to the side to make room, and are sometimes prone to spilling water. I love my Gibson guitar, and I love knowing it has plenty of humidity in the case.

I believe this is my first review out of the hundreds of products I have purchased on Amazon.com. I have two guitars. Both are kept in a room that, according to a "Caliber III" hygrometer, has remained between 50 and 55% humidity over the past three months. I have maintainted the full humidipak system on both instruments and have had to replace them twice in the past three months because they had hardened.Based upon the advertised performance, using humidipaks in a room where the humidity is slightly higher than the 45-50% recommended range made perfect sense: The packs, though open, would only absorb, not relinquish moisture. There should have been very little if any exchange. Apparently, that is not so.At $30 per month for humidipaks, I believe I can amortize the cost of two instrument humidors. Great concept, but even under the best of conditions these things only last 45 days!UPDATE: I just re-read my review. I'm still using humidipaks--better than nothing I'm telling myself--but I've charted the humidity in the room where I store my guitars. For the past month it has not dipped below 55% but the humidipaks are still hardening. Don't know why. Still telling myself they're better than nothing, but if humidity is higher than 50%, why are they hardening????UPDATE: 3-22-13For the past year I have been re-humidifying the humidi paks in a manner referenced in another review and this has worked out very well. Now they seem to last indefinitely. I still purchase new ones as back ups. I don't know if the membrane that keeps the gel inside has a shelf life (a couple of packs I received from Amazon had exploded within the cellophane bag) so I'm keep a close watch on their condition. But so far, this system seems to work great.Update 3-15-15WARNING!!! PRODUCT IS NOT THE SAME AS PICTURED. THE DOUBLE POUCH SOUND HOLE PIECE HAS BEEN REPLACED WITH A SINGLE POUCH!! I bought a new guitar and ordered a new D'Addario Humidification Kit. The new ones come with a new sound hole system that only has one pouch. The trick is to secure it with two plastic pieces then slide it between the D and the G string. It's a JOKE! No matter how I secure it, unless I roll the top of the gel packs into the part of the pouch that's supposed to fit into the plastic securing pieces, the pack sits on the inside back of the guitar and the plastic pieces are loose enough to move around and mar the finish on my guitar. The package says "New and improved" because the pouch is less likely to permit any leaking humidpak to leak into the guitar, but I don't know why they couldn't have achieved that with a double pouch system. I just drove up to my local guitar store to get a system with the double pouches to ensure I got them. I ordered what was pictured from Amazon and got the singe pouch system. I love humidipaks, but I hate the new single-pouch sound hole sleeve.Bill

These have saved my instruments through many winters and humid summers. Absolutely can’t recommend these enough! When they get crunchy in the winter, I replace them with a fresh one. Haven’t had to setup any of my acoustics since using these.

I have used these for years. My two guitars stay in tune much longer in spite of extreme weather changes and humidity changes.

always a value