The GER Class 209 (LNER Class Y5) was a class of 0-4-0 saddle tank steam locomotives of the Great Eastern Railway. These locomotives were similar to the NBR G Class but had flat-topped, instead of round-topped, tanks. A total of eight were built – four by Neilson and Company in 1874 and four more by the GER's Stratford Works between 1897 and 1903.