These Extended Range pH strips give the user an accurate alternative to pH meters without sacrificing quality results. Since all required reagents are precisely impregnated on the strip pad, there is no need for calibration. Utilizing a dual-pad indicator system is what makes this pH test unique, both indicators are designed to work in unison, providing a wide range of color development. Additionally, the dual-indicator system makes color matching easier and more reliable since both colors are uniquely different from each other.