The Cortebert 519 is a manual wind watch movement that was used starting from 1927. It is associated with the signature "Gruen 106" and is believed to have similarities to the Gruen 1067 movement. The specific differences between these two movements are not known, but it is speculated that they may be related to differences in the base-plate shapes, such as round corners or octagonal. The movement features a bimetallic screw balance and a Breguet hairspring. The frequency at which this movement operates is not definitively stated, as there is a discrepancy between the information provided by Flume and the details found in Gruen catalogs.