This Directional Carb Cap from Pulsar is made to fit most quartz and titanium banger nails. Made with worked borosilicate glass in a multicolor striped pattern and a UV reactive stripe. These bubble shaped carb caps provide directional airflow while you are dabbing. Being able to direct the airflow helps ensure that you get the most efficiency with your concentrates and they get completely vaporized. Diameter measures 27mm wide.