Acidity levels: Abbr., 3 letters
Acidity measures, 3 letters
Acidity nos., 3 letters
Acidity ratings, 3 letters
Acidity-level symbols, 3 letters
All F's in this puzzle, 3 letters
Basic ones are over seven, 3 letters
Chem. class measures, 3 letters
Litmus test nos., 3 letters
Measurements of alkalinity, perhaps, 3 letters
Measures of acidity, 3 letters
Measures of alkalinity, 3 letters
Rehab regimen (8,7), 9 letters