WHY THIS BOVEDA: 4 STANDARD REPLACEMENT PACKS FOR BOVEDA STARTER KITS\u2014SMALL, LARGE & DIRECTIONAL & TO FILL BOVEDA SINGLE & DOUBLE FABRIC HOLDERS. Protects fretted, bowed & woodwind instruments from humidity fluctuations. Maintains the ideal humidity level in an instrument case. NATURAL INGREDIENTS. Trusted by over 3 million people to protect & maintain items at the perfect humidity level. WE GUARANTEE QUALITY If you\u2019re not 100% satisfied, reach out for a full refund for up to 1 year. HOW BOVEDA WORKS FOR MUSICAL INSTRUMENTS: Boveda 49% RH protects wood instruments & their accessories by stabilizing the humidity within the ideal range\u201445\u201355% RH. If the air inside a case is too moist, Boveda absorbs that moisture. If it's too dry, Boveda releases small amounts of water vapor into the case. Wide humidity fluctuations will cause the wood to expand or shrink, which puts stress on the instrument & degrades its performance abilities. CHOOSE BOVEDA: Boveda's the only patented 2-way humidity control solution with 25 years of experience. Using saltwater in our humidity packs, we provide the fastest, most precise humidity control in the market for wood instruments. When you invest in an instrument, you want to ensure you take care of it to produce optimal sound. Boveda is the only humidity solution that can do so within 24-48 hours. HOW TO USE: Always insert Boveda packs into a protective Boveda Fabric Holder before using in an instrument case. Boveda Fabric Holders are available separately & in Boveda Starter Kits. Remove a pack from the resealable bag. DO NOT cut or open the brown humidity packet. Slip the packet(s) into the holder(s). Place in case and close the lid. BOVEDA DOES THE REST. Replace every 3 months. You'll know it's time to swap out Boveda when it becomes hard & crunchy. NEVER MIX the 49% with any other %RH. WHO IS BOVEDA FOR: Boveda 49% RH is for acoustic & electric GUITAR players & musicians who play WOODWINDS & BOWED INSTRUMENTS. Professional musicians, band & orchestra leaders, instrument techs, music teachers, hobbyists & student musicians use Boveda packs for easy & precise humidity management for instrument storage. NO DAILY MAINTENANCE Don\u2019t risk damaging an instrument by adding water to sponges and snakes & forgetting to refill them. WHY RISK A WARPED OR CRACKED INSTRUMENT?