Leica Ic 'PTT' with Summaron 3.5/3.5cm

Very rare Ic modified and used by the Dutch postal office and engraved 'PTT' for Posterijen, Telegrafie en Telefonie (Post, telegraph and telephone) close to the serial number, in almost mint condition, delivered to retailer Odin, Nijmegen (Netherlands) on 03.10.1951, note the longer bayonet to film distance modified with a nickel plated ring, all speeds are selectable, with Summaron 3.5/3.5cm no.1015956 with matching 'PTT' engraving, good optics only showing a few light cleaning marks, focus and aperture setting are not fixed, with front lens cap.