ShieldPro Humidity Indicator Card 3-Dot 30-50% for use with Desiccant/Moisture Absorber in Gun Cases, Camera Cases and Scientific Uses (50) This Indicator Card has 3 indicating spots (30/40/50% RH). Indicator spots change from Blue (dry) to Pink (humid). Reversible Humidity Indicator Card (reusable) Reliable protection brought to you by ShieldPro and Discount Mylar Bags. Ships same day.