pH-Fix 6.0-10.0 indicator strips with chemically bound indicators are the bench mark for pH testing with test strips. The fixation prevents bleeding and therefore contamination of the sample. measuring range: pH 6.0-6.4-6.7-7.0-7.3-7.6- 7.9-8.2-8.4-8.6-8.8-9.1-9.5-10.0