Volumetric Pipette provided by STE-Mart has a bulge in the middle. The upper and lower ends are connected with slender glass tubes, and the upper tube is engraved with a circular line of nominal capacity. The lower tube is slender and is drawn into a conical discharge nozzle, which is easy to reach into the measuring bottle and other small-mouth containers to absorb the solution. The middle expansion is to increase the storage volume and shorten the length of the pipette, which is convenient for use.