7Zap question

[BackintheFold]

OK, I've been using 7ZAP for a short time, and it is very helpful.
However, please can someone explain what the codes are in the "Title" section of each page?

As an example, what does
F85-D-900 001 - 902 500
signify, and how does it compare with
F85-E-900 001->
?

I thought the numbers would relate to chassis number, but they do not-because the "D" and "E" in the title allow identical numbers to feature in two sections. eg, chassis No.900200 would sit in both of the two titles shown above.
It is confusing me, and making it impossible for me to tell if I need (for example)
part 857 000 111 A, or 857 000 111 F

There must be a simple, obvious explanation that I am just not getting...

Many thanks!