Boveda for Music | Double-Sleeve Fabric Holder for 49% RH Boveda 2-Way Humidity Control | For Use with 2 Boveda Size 70 to Protect Large Instruments from Cracking/Warping

Insert one Boveda in each slot on the saddle and drape over the strings into the sound hole. Step 2: Insert one Boveda in each slot on the saddle and place it near the headstock. Boveda then goes to work responding to ambient humidity by adding or removing moisture as the conditions require to maintain the perfect 45-55% environment for your instrument. And because Boveda requires no activation or maintenance, you'll spend more time enjoying your passion. When the Boveda lose most of their soft spots, it's time for replacements. Pro Tip: Your case needs moisture, too. Keep the Boveda closed tightly in the case while you're playing.