Side elevation of a telescopic gangway for boarding by plane.
A boarding sleeve, also known as a telescopic gangway or boarding bridge (sometimes called the English word finger, literally "finger", is a closed mobile connector, which connects an airport terminal gate to an aircraft. to get on and off the vehicle faster than the ladders. Depending on the design of the buildings, the boarding sleeve can be fixed or mobile: it can in fact move both vertically (rising or lowering), and horizontally (lengthening and shortening).
The catwalk, in English jetway, was invented by Frank Der Yuen.