Have you been looking for a kit to add an electronic horn to your diesel?
This is a neat kit that Lionel put out in 1981 to upgrade your sound-less diesel to a one with horn sound. This one was released to go in your F-3 B unit. It likely has other diesel applications, but that would be up to you.
As you can see, this one has all the components you need: board, pick up with roller, speaker, instructions, etc.
This is a resource you do not see offered for sale very often!
CONDITION: C-8 like new unused. It is all here. Contents like new. The foam tape has disintegrated due to drying out as it always does (even when installed!). Box shows some shelfwear. Instructions have been creased, etc.
Grab it while you can!