Tired of finicky 510 threaded chargers? So are we. Our Dual Charge vape battery is a classic 510 threaded vape battery that is compatible with BOTH 510 threaded chargers and USB ports. We have found that a separate charging port increases the life span of your battery and does not subject the charging connection of your vape products to additional wear and tear. 1. 15s rapid preheating function 2. 3 adjustable voltages (green 2.6V, blue 3.3V, red4.0V) 3. Supports both USB and 510 threaded chargers. Compatible with all 510 threaded cartridges and chargers.