Weapon Categories and Starship Weapons

[ChalkLine]

This is driving me nuts.
I know I've seen this somewhere. If you agree with it or not I've seen that pulse lasers are considered 'category four' weapons in Mongoose 2 rules. I'm absolutely sure I've seen particle weapons referred to them as such but I can't find the reference.
I've had no luck using the 'find' function, am I going mad?

 

[AnotherDilbert]

Do you mean the Black Market categories in CSC (p5)?

 

[Old School]

According to Traveller Companion p. 136 pulse lasers are category 3. Torpedoes, particle beam, plasma, and fusion spaceship weapons are Category 4. Category 5 ship mounted weapons are Meson and Ortillery.