Form movement Technical term for a movement that is not round but instead shaped in the form of the case. Form movements can be rectangular, tonneau-shaped, or arcade-shaped, for example.

For Lange, this watch is equivalent to the quadrature of the circle. It is a rectangular timepiece that displays the date almost five times more legibly than other mechanical watches of comparable size. Its custom | form movement fills the case with exquisite Lange watchmaking artistry to the very corners.