What is the pore size (microns) of the purifier cartridge?

Pore size is not relevant to G3+™ technology; it's like asking how much horsepower a laptop computer has. Pore size is relevant in 'mechanical filters', which work by forcing water through tiny pores in a filter. In a mechanical filter, the biggest pore must be smaller than the smallest germ. The downside of mechanical filters is that tiny pores prevent rapid flow of water, so they work slowly or require lots of pressure. Instead, G3+™ technology uses electroadsorption; relatively large pores overlaid with a positively-charged mesh (think little magnets) that latch onto germs. The result is fast-flowing, clean water so you can #PurifyWaterAnywhere.