Do you feel like your vape is starting to have a tighter circulation for the air? Are your vaping sessions not as good as in the past? Then it is probably time to replace your screen set. Your vaporizer is likely experiencing buildups that are blocking the screen and preventing you from exhaling the vaporized liquids. These screen sets have different textures to regulate the airflow. Of the six screens, four are upper screens with a coarse mesh while two are lower screens with a regular texture. The screens are durable and can last a long time. A regular maintenance brushing is recommended for optimum performance.