The funnel has a 1000 ml capacity and is made from borosilicate glass. At its base is a sintered glass filter disk with micro-pores approximately 16-40 µm in size. These pores allow brewed coffee to pass while holding back the grounds, delivering a clear, aromatic cup without the clogging or flavor retention common with cloth or ceramic filters. The transparent construction also gives the brewer its distinctive, laboratory-inspired look.
