A perspex box conaining plastic strips with indicator paper at the end
- Made:
- circa 1980
A perspex box conaining plastic strips with indicator paper at the end . These precision indicators made by Merck & Co., Inc. range pH 2.5 - 4.5.
A perspex box conaining plastic strips with indicator paper at the end . These precision indicators made by Merck & Co., Inc. range pH 2.5 - 4.5.