Simplex F660DT

Just bought this off of eBay… it seems to be exactly like a 4263-1, but normally closed. The model label reads “F660DT.”
Pics… later.

Okay, so it turns out that it wasn’t normally closed. The contacts that the code wheel hits were backwards.
Still strange about the model number, though.

I believe F660DT might be the original Couch / Faraday model number, not the Simplex one.