The 18 series had the square buttons on the control panel at least on the top of the line, and the 19 and 20's had the oblong shaped buttons. Would have to check the sales brochures. Peteski, are you out there?
I am positive that this is a 20 series...Energy Saver V model KDC-60. I have the built-in model equivalent in my basement and the button configuration matches mine. The 19 Custom model I believe only had 2 buttons - Normal Wash and Rinse & Hold.
The 20 series had 4 buttons - Heavy Wash, Low Energy, Rinse & Hold, and Energy Saver/No Heat Dry option.