 The O 'Brien class of destroyers was a class of six ships designed by and built for the United States Navy shortly before the United States entered World War I. The O 'Brien class was the third of five classes of destroyers that were known as the " thousand tonners " , because they were the first U.S. destroyers over 1 @,@ 000 long tons ( 1 @,@ 016 t ) displacement . 
 The O 'Brien class of destroyers was a class of six ships designed by and built for the United States Navy shortly before the United States entered World War I. The O 'Brien class was the third of five classes of destroyers <a href='null_relcl' title='1'><mark>that</mark></a><a href='uninflect' title='2'><mark>were</mark></a> known as the " thousand tonners " , because they <a href='uninflect' title='3'><mark>were</mark></a> the first U.S. destroyers over 1 @,@ 000 long tons ( 1 @,@ 016 t ) displacement . 
The O 'Brien class of destroyers was a class of six ships designed by and built for the United States Navy shortly before the United States entered World War I. The O 'Brien class was the third of five classes of destroyers was known as da " thousand tonners " , because they was tdafirst U.S. destroyers ova 1 @,@ 000 long tons ( 1 @,@ 016 t ) displacement .