Lufterators are seen in Book 4: Neverseen. They are a gadget that allows the user to breathe underwater. Sophie first sees them because she has to ride an eckodon. Due to the fact that Della came without Mr. Forkle knowing, there isn't enough for all of them. However, Dex tweaks his Lufterator so that two can use them. Mr. Forkle notes that the users would have to keep their mouths very close together, which causes Keefe to volunteer him and Sophie. Dex volunteers too, but Mr. Forkle decides that Dex and Keefe will share.