Dry-Packs Silica Gel Desiccant, 40gm Silica Gel 2 x 4 1/2 Inches Sturdy Aluminum Housing Moisture Indicator lets you know when you need to bake to reactivate Cobalt Chloride Free - NO BLUE SILICA GEL Identical Size as the Pelican 1500D Peli Desiccant