A Magic Wand for Espresso
topics.blogs.nytimes.com/2009/04/30/a-magic-wand-for-espresso
From the page
Saved with the link. Notes from 2007 to 2016 are mostly the page's own words, so this is probably an excerpt.
Twist uses a standard carbon dioxide cartridge to force water through the filter basket – the 9 bar pressure comes entirely from the cartridge, which is regulated by a sophisticated mechanism hidden in the handle. Squeeze the trigger and a perfectly dosed espresso streams out of the spouts, a 30-second extraction with a rich crema.