Had a good look at the 121 yesterday ans hats off it looks fantastic , when you see the model laid out with the various cabs you forget how many variations there were of the 121 class , large centre window small centre window , handrails , no handrails , vents in doors no vents the list is endless but I think Paddy Murphy has got it correct . Price aside these locomotives are a must have for any Irish Modeller . I hope some of the transfer makers SSM and Railtech will do a transfer pack of alternative numbers for the 121's so we can alter the fleet number to suit in my case Black and Tan B121+B134 which were the first pair of 121's.