... contain cobalt chloride and is therefore innocuous and pollution-free,3 Its color varies as humidity changes.Use:Mainly for drying ... purplish redeligibilityRH=90%light redeligibility Size :1-3mm,2-4mm,3-5mm,4-8mm Packag: 25kg compound bag or 25kg drum, special ... Product Picture: Package: Refined type A blue silica gel size: 3-5mm, 4-6mm, etc