These carb caps are shaped like a thermal cap with a cyclone airflow nozzle for spinning thermal pearls. They feature two different air intake holes which create multiple functionalities from one cap. Plug the hole on the side of the bubble and the cap functions with cyclone airflow. Plug the hole on top of the handle and the cap function like a standard bubble cap. 55mm (tall) x 30mm (wide) x 2mm (thick). “For tobacco use only”.