DuvinDD 18 Pack pH Calibration Solution Powder 6.86/4.00/9.18, pH Buffer Calibration Solution Packets for Precisely Calibrate pH Meter, pH Tester Calibration Powder Packets

Suitable with most of pH meters, Ideal for Calibrating
pH buffer calibration solution powder accuracy is plus or minus 0.01pH, accurate and precise
Individually wrapped to maintain freshness until use. Made with qualify materia
Easy to use: Mix the buffer powder with 250ML distilled water, put the pH meter in the solution and gently stir and wait a few seconds for the result
18 pack ph calibration packets: 6*ph 6.86 packets, 6*ph 4.00 packets, 6*ph 9.18 packets, cost-effective and flexible for using