Our cartridges are 510 threaded to fit congruently with all of the wholesale batteries and vape pens that we offer. 510 threading is the standard or “universal” threading used on the majority of bulk vape cartridges. The same is true about most vape batteries. The 510 threading refers to the male threading on the bottom of the cartridge and the female counterpart on a battery. Although rare, vape pen cartridges also come with 710 threading. The difference is the thread count on the bottom of the cartridge. Adapters are available to pair the 710 thread cartridges with 510 batteries but it is suggested to purchase both in the standard 510 formats to avoid any confusion.