Burets are the main measuring instruments used in titrimetric analysis, which can be divided into two types: acid burets and basic burets.

The basic buret is used to hold alkaline solution. Its lower end is connected with a rubber tube. Glass beads are placed in the rubber tube to control the flow of solution. A pointed glass tube is connected to the lower end of the rubber tube. Any solution that can react with the rubber tube, such as potassium permanganate, iodine and other solutions, cannot be put into the basic buret.