On this list the "Front" of the slide rule is where the Name and Number are most prominently displayed. The "Front Cursor" is also on this side. There are exceptions, such as where the name is on one side and the number on the other. On some, where I had a copy of the instruction manual available, it defined what was Front and Back.
Where there are two entries such as "S & S" it denotes there are Black and Red numbers on the same scale. This makes the scale actually two scalesr, usually one being the complement of the other. As an example, in the case of "S & S" the degrees are shown as 10 80, and 70 20, etc. At least one rule has Black and Black complementary numbers. However, all scales are in black where I do not own or have a color picture of the slide rule.
The CF and DF scales are all folded at π, unless noted that they are folded at √10, or other value.