• Ensures water hardness: The water hardness test kit helps you control water hardness to prevent corrosion, scale formation, cloudy water, or excessive foam. • Multi-purpose: Ideal for water filtration systems, aquariums, pools, spas, laundries, cloth diapers, dishwashers, industrial processes, educational experiments, and home protection applications. • Quick and easy: Dip the test strip, wait 15 seconds, and get instant results. Read the results between 15 and 30 seconds and compare them with the included color chart. Do not interpret after 30 seconds. • Long-lasting: Each kit contains 20 strips for a variety of uses. • BMUT testing experts: We have a professional research center, a high-efficiency factory, and an online after-sales service. • Product dimensions: 6 cm wide, 0.5 cm high, and 12 cm long.