this is a box style vape battery from the Yocan company. It is the only one they offer but it gets great reviews. You can adjust it to take any diameter oil cartridge sold at dispensaries. It comes with two differnt metal magnet sleeves that you screw on the bottom of your vape cartridge depending on how long the cartridge is. It makes the contact with the battery through the magnet rather then screwing the cartridge onto the battery via the 510 thread. This makes this style of battery so much more durable then a screw on type.