The records were transferred from the Admiralty between 1961 and 1977 and are known by their Public Record Office class, ADM/170. They consist of technical specifications for naval ships built in the Royal dockyards, and contain details of the quantities and qualities of materials to be used and the dimensions of the ship's structure. They are similar in content to the Ships' Contracts (entry no.6, ADM/168), except that they omit the contract preamble and closing sections. The series begins with a listing of the scantlings of the 1719, 1741 and 1745 Establishments and extends to the end of the Second World War. Until the mid-nineteenth century these documents are in manuscript; thereafter they were individually printed. The Admiralty collection of ships' plans, held in the Draught Room, occasionally includes specifications similar to those described here, together with occasional letters and memoranda concerned with design or building.