The 139 was produced from 1939 to 1951 and is highly sought-after among collectors. Pure asking prices on eBay (e.g. 4600 USD) are not meaningful, since what matters are the actually realised sales prices, which fluctuate strongly depending on condition. Decisive for the value are in particular the colour of the ink window (as light as possible, the darker the lower the value), scratches and cracks, the condition of the cork, the nib type (e.g. ball nib, KOB imprint), the presence of packaging and papers, as well as whether the piece is NOS (never used). eBay reaches the largest collector target group for the sale.