Standard port instruments are a type of glass instruments with uniform caliber for chemical experiments. They can generally be divided into different calibers such as 2#, 4#, 6#, 8#, 16#, 24#, and 32#. The characteristic is that instruments of the same caliber can be freely combined with each other to form different devices. Standard port instruments are mostly used in organic synthesis experiments, mainly including flasks (mostly 2 or 3 ports), glass stoppers, mercury thermometers and sleeves, condenser tubes, conduits, piston tubes, constant pressure dropping funnels, etc. Before using the standard port instrument, check whether the frosted port is complete. When connecting it into a device, wipe some water on the interface to ensure a secure connection and airtightness of the device.