Scale 1:48. Plan shows a plan view and sections, as fitted, of the M-class submarine M3 (1919). The drawing shows section Frames 10, 25, 49, 67, 85 and 92 looking forward and Frames 100, 117, 138, 150 and 159 looking aft. The plan shows modifiactions in vermillion ink at Chatham Yard dated January 1929. A note on the drawing statres to see the Fly diagram to the minelayer arrnagment for the vessel. There is a Armstrong Naval yard stamp dated 16 February 1921. A second Admiralty stamp bearing the signature of the Ship Overseer "T. H. Bentley", dated 5 September 1921 is situated undeneath the first stamp.