You are bidding on a "Knotmaster" Ship's Log Mark IIIA made by Thos. Walker & Son, Ltd, 58, Oxford Street, Birmingham, B5 5NX . This is a time-honoured device for measuring distance traveled. You tow one of the impellers behind the meter, which clamps onto the stern of the boat; as the impeller turns, it turns the meter (via its towing line) which clocks up the miles. The dials are (left, right, and main) tenths, units, and tens of nautical miles, up to 100 miles (presumably the navigator will remember to check it at least that often. or be thrown overboard). This log comes with 2 starboard mounting shoe,s two spinners, 2 sinkers, two lines extra spare clips and brackets . It also his original fitting and maintenance intrucctions papers This set looks unused and brandnew and so it has got no corrosian from seawater. (See all pictures) Carefull Shipping with track/trace