Hinges GN 129 are used for doors which are flush with the frame on the outside. The hinges are normally arranged to the side of the door.

In the two-part design, the door can be unhinged with two identically arranged hinges.

The three-part hinges, which generally cannot be unhinged and are mounted inside, are suitable for doors and flaps which, as anti-tamper precaution, must not be dismountable from the outside.