Carb caps are a lid for your dab nail or banger, this serves many purposes including directing the airflow and vaporizing your dabs at a lower temperature. A glass carb cap will help you get the most out of your oil rig and concentrates. Watch your dab turn milky white as soon as you drop the dab cap on the banger. It’s no wonder that a good dab cap has become the most essential accessory for dabbers. This is for all those wasted dabs that just melted away and never really smoked up. We want that tube to turn milky white, and that is what a directional carb cap can do for you.