Abstract: A pressed thermite rod for a self-contained portable cutting device is disclosed having a longitudinal section of a rectangle shape and a cross-section of an elongated shape on its entire length with a height to width ratio ranging from 1.2 to 2.0 and with long sides parallel at least in their middle section. The cross-section of the pressed thermite rod may be close to rectangular. In other embodiments, the pressed thermite rod has a rectangular cross-section with rounded corners; convex rounded short sides; or rounded corners at a first short side and a convex rounded second short side.