The Integra Boost Humidifier 67 Gram Pack 72% is the maintenance-free, eco-friendly way to ensure your favorite cigars stay fresh. Its responsive Integra BOOST (TM) system quickly releases or absorbs moisture as needed to ensure your humidor maintains its ideal humidity level. To use, simply place the pack in your humidor along with the Replacement Indicator Card. When the dot on the card turns blue, it’s time to replace the pack. Use one pack for every 50 cigars your humidor can hold, plus one additional pack (for example, 2 packs for a 50-cigar humidor, 3 packs for a 100-cigar humidor).