This is a fairly large 1940s 35.5mm chrome-plated and stainless-steel-back Nisus chronograph. Look at the very interesting large and flat pushers. The movement is the fine and famous Valjoux 23 column-wheel chronograph, which was just serviced and is working perfectly. The dial has acquired a fine patina over the years and retains the original blued steel pencil hands and sweep seconds. Notice the multi-coloured red-and-blue outer scales. The case displays excellent overall condition. This is a very fine vintage chronograph that will provide many more decades of enjoyment on your wrist.