Lionel 621-121 Horn Relay - Above you will find a single stock view picture of a Lionel 621-121 Horn Relay as used in Lionel's 218, 220 and 226 sheet metal frame diesel locomotives. Generally Lionel would change the original part number from 2333-121 to 621-121 and so on after final assembly as they were pre-wired for the assembly line, with some having different ground wire lengths. The horn relay shown consists of original units that have been rebuilt with new old stock components, and we guarantee it to work as intended. some of the relays are not bright and shiny, but function as new. In many cases we rebuild these relays as necessary. Although our original relays cost a bit more, this is a steal as it comes with a guarantee! There isn't any "as is where is" with these!