The Kind Pen Twist — VV 510-Thread Vape Battery (Choose Color) Twist is the only 510-thread VV battery you’ll ever need. It’s compact and portable (but powerful), and it works with most 510 cartomizers and tanks. (We advise against using it with big tanks as they will make the pen very top-heavy. Also, Twist works best with less viscous oils and liquids.) The capacity of this battery is 400mAh, and it features a LED indicator light that will tell you when the time comes to plug it in. Charging is done via a universal USB charger. TWIST 510-THREAD BATTERY SPECIFICATIONS: 400mAh battery capacity A 510-thread battery compatible with most carts and tanks Simple, one-button operation 2-click preheat feature (2.0v) Variable voltage capabilities (2.0v-4.0v) Battery life LED indicator Universal USB charger Select options