A graduated serological pipette, Class B, is a type of laboratory pipette used for measuring and transferring precise volumes of liquid. It is called “serological” because it is commonly used in the serological (or biological) analysis. The pipette is calibrated to Class B standards, which means that it has a permissible error of ±0.1 mL or ±0.2 mL, depending on the size of the pipette.

Graduated pipettes are marked with precise volume markings, allowing for the accurate measurement and transfer of small volumes of liquid. They are commonly used in chemistry and biology labs for tasks such as titrations and the preparation of solutions.