Buyers must prioritize the Total Fluorine content (typically ≥12.7%) and the Free Fluoride content (usually <1.2%), as high levels of free fluoride can affect formula stability and safety. Ensure the particle size meets your production needs, typically 95% passing through an 80-mesh screen for seamless integration into toothpaste pastes. Additionally, verify the pH value of a 1% solution, which should ideally fall between 6.5 and 8.0 to ensure compatibility with other ingredients like calcium carbonate or silica.