Sodium hexafluorosilicate is usually commercially available in technical and C.P. grades; it was formally available in insecticides of up to ~98% purity such as granular baits. A typical product contains 59.34% fluorine and a maximum of 0.50% each of water moisture, water-insoluble matter, and heavy metals (as lead).
Fluorosilicic acid is commercially available as aqueous solutions (up to 70%) in technical and C.P. grades. A typical product contains a maximum of 23% of the acid, a minimum of 18.22% fluorine, a maximum of 0.02% heavy metals (as lead), and <1.00% hydrofluoric acid. Many U.S. producers and suppliers are available for both compounds (over 20 for each).