The Industry's First Stackable .510 Cartridges. With EXSTAX Patented Stacking Technology you can now combine (2) two .510 cartridges to create a one-of-a-kind product experience pairing your favorite cartridge brand, oils, flavors, and strains with EXSTAX Stackable Cartridges to build custom combinations you can only find get with EXSTAX. Inspired by community, collaboration, and innovation EXSTAX amplifies the user experience creating new connections in community, cannabis, and technology. #STAXONSTAX