Dymo M-55 Tapewriter

I won an auction for a used embossed tape labeler, a Dymo M-55 that was made sometime in the 1960s. It's all metal and chromed, and pretty sweet. Interestingly there is no numeric "1" or "0" on it; I guess you're supposed to use the letter "I" and "O" as a substitute! Saves space for other symbols!