The Moccamaster KBGT is a thermal coffee brewer while the KBT is a pourover coffee brewer. The main difference between the two is that the KBGT maintains water at a consistent temperature, whereas the KBT does not. This means that the KBGT can brew coffee more quickly and evenly, but it also means that it requires more cleanup than the KBT. The other main difference is that the KBGT has a glass carafe while the KBT has a plastic carafe.