What is the fine-grained topic of the following text: RMT now offers an LIRR RDC in 2 different numbers...1834 and 2009 to commemorate the anniversary...each featuring the unique 'Dashing Dan' commuter logo on the RDC's sides along with the '175th Anniversary' logo. Only return the topic.
RMT's LIRR RDC models commemorating the 175th Anniversary