Scale 1:48. Plan shows the starboard inboard profile, looking from port, an internal plan view below the flats and sections, as fitted of the U class submarines Unbroken (1941), Unison (1941), United (1941), Unruffled (1941), Unrivalled (1941), Unshaken (1941), P42 (1942) and Unseen (1942). A Vickers Armstrong builder's stamp, dated 15 MArch 1944 is printed on the drawing. A Vickers Armstrong Principal Ship Overseer's stamp, dated 20 March 1944 is also printed on the plan. The drawing shows the sections at Frames 10, 20, 31, 46 and 64 looking forward. The plan also shows the sections at Frames 72, 82, 92, 102 and 113 looking aft.