The IWC 53 20 watch movement is a manual wind movement with sweep seconds. It belongs to a family of movements that includes the Femga 500 and 502, as well as the Precimax 250, 250SC, 400, and 450. While there is a strong resemblance between these movements, their relationship between the French Femga and Swiss Precimax remains uncertain. Further investigation and examination of samples may provide confirmation. The IWC 53 20 movement was primarily used around 1945.