D'Addario Guitar Humidifier Pro, by D'Addario, White

I got these in the hope of upgrading the sponges in my existing humidifiers as they are meant to hold more water, which certainly seems to be the caseWhile not specifically designed for the original D'Addario/Planet waves humidifiers, they fitted both of mine, although the fit is a little tight when dry. The newer pro humidifier that comes with these sponges as standard has a little more room, but they certainly work fine in the old ones, so if like me, you're getting tired of soaking the sponge daily, give them a try.I found leaving them to soak for a few minutes gave the best results, unlike the original sponges, you can't just run them under a tap...