Most of the static world drop armor and weapons have only four versions, even though there are dozens of different names. There are force and tech versions for both the Empire and Republic (only force versions for light armor). Modifiers listed at the beginning of the item name indicate the tertiary stats that are available for the item, eg. Adascorp Expeditionary Cap (power and accuracy) and Colla Designs Expeditionary Cap (critical and accuracy).
The low level armor sets only have two-five modifiers since they don’t have tertiary stats. Also, there are blue Prototype versions of the same sets that may or may not look different.