Activated carbonis a form of carbon processed to have small, low-volume pores that increase the surface area available for adsorption.

Due to its high degree of microporosity, just one gram of activated carbon has a surface area in excess of 500 m2, as determined by gas adsorption.
Activated carbon is usually derived from charcoal. It is widely used in gaspurification, decaffeination, gold purification, metal extraction, water purification, medicine, sewage treatment, air filters in gas masks and respirators, filters in compressed air and many other applications.
The coffee maker water filters that Jietai produces are made of  high quality coconut shell charcoal activated carbon, removing chlorine, magnesium, calcium, etc. The filtered water will make your coffee taste much better.