From the back cover:
Traders and Gunboats provides details of over fifty space going vessels for use in the Traveller game, an extensive roster of ships that every Referee will find invaluable in running their campaigns. These are the ships that Player Characters are most likely to interact with, civilian and military craft of no more than a few thousand tons that undertake a wide variety of roles.
Each ship is fully detailed, with statistics, schematics, and illustrations all adding to the basic description of the craft. From pirate raiders, prison security ships, and system defence boats the array of small military craft is wide ranging. Civilian craft include the ships that form the express boat network, safari ships, salvage vessels, medical craft and more.
With this invaluable aid the spacelanes of the universes of Traveller will now be filled with all types of starships, from the everyday to the exotic.