DRY&DRY Half(1/2) Gallon Replacement Desiccant Indicating Silica Gel Beads Reusable, Blue 30+ Year Experience in the Industry of Silica Gel Desiccant - Premium Quality(See Our Customers' Reviews) Half Gallon Volume of Fresh Blue High Quality Indicating Silica Gel Beads(Approx 3.7 lbs) , Silica Gel Bead Size: 2-4 mm Indicating Silica Gel will turn Blue to Pink when 50-60% absorbed with moisture. Still almost half more capacity left to absorb moisture even after color change. Blue Beads contain "COBALT CHLORIDE" which may pose health risk and environmental issues. Our blue beads contain only 0.005% cobalt chloride Beads can be Reactivated by Placing in the Oven for 0.5-2 hours at 200-250F Or Microwave for About 10 Minutes at DEFROST. Don't use over 250F in the Oven. Depending on beads' condition, they may take shorter than the recommended time. Please check the beads' color periodically.