I've never
even seen pictures of it. I can imagine that this option
existed but that most people didn't get it because it cost extra?
There were zillions of options for most every model Teletype (probably
the most for 28s), including some really wild ones (two color printing
and on-the-fly speed changes being some of the more bizzare).
Well at one time two color printing made sence. Oddly I picked up
some surplus caps ... 5uf 330 VAC, .033 uf 600 V and they where
Teletype spares of some kind.