For use with any 510 threaded vape cartridge, Grassdoor's Soft Black Battery is a slick, adjustable voltage device that's great for streamlining your experience and getting the most out of your concentrate.
How to Use:
-5 Clicks to turn on/off
-2 Clicks for preheat
-3 Clicks adjusts voltage between 2.7v, 3.4v, and 4.0v