Made naturally with sun, wind and time. Our solar salt water softener crystals are a 99.6% pure and a natural choice for treating your hard water. It's a great way to put nature to work softening your hard water. Diamond Crystal Solar Naturals Water Softener Salt Crystals have a white, opaque appearance. Solar Naturals Salt Crystals are recommended for use in all water softenersTypical 99.6% pure salt (sodium chloride)Made naturally with sun, wind and timeSolar salt crystals are naturally white and opaqueLow insoluble contentMinimize accumulation of tank residueRecommended for use in all water softenersPackaging made of 50% recycled materialsNSF certifiedFeatures:Container Size: 40 poundNSF Listed: YesPackaging Type: BaggedProduct Form: CrystalSub Brand: Solar Naturals