The Freemax Fireluke Pro Tank utilizes the FireLock Coil System and the bubble glass formation that can hold up to 4ml of your favorite juices. This tank provides dual airflow slots at the bottom of the tank to customize how much airflow you prefer. Freemax Fireluke Pro Tank Tech Specs Diameter: 25mm Capacity: 4ml Fill: Threaded Top Fill Airflow: Dual Bottom Adjustable Airflow Slots Drip Tip Size: 810 Drip Tip Material: Resin/Carbon Fiber Included Kanthal 0.15ohm sextuple coil Pre-installed (60-120W Recommended Range ) KA1 DVC 0.25ohm Coil Head (50-100W Recommended Range) Replacement Glass Tank Section (4ml glass tube) Spare Parts Pack User Manual WARNING: This is an advanced user item. Use at your own risk! Please ensure that proper precautions are taken when using such devices. There is an inherent risk with the use of any and all rechargeable batteries in any circumstance. Please read and make sure you understand the users manual before use.