The usage of article in this sentence

[Pavlik]

Hello everybody,
I would be very grateful if someone could help me out with this sentece.
"It is said that the Vatican gave Croatia a loan of 10 million dollars for a military equipment to fight Serbs".
My teacher crossed out "a" in the sentence in bold. The problem is, I am not sure whether to use a definite article or zero article here. I've always been under impression that uncountable nouns modified with an adjective may take an indefinite article . As for the context, there is no other reference to the equipment in the following or previous parts of the essay.
I would be really grateful for any kind of help,
Thank you

[Alan]

Only certain non-count nouns can be treated as countable if adjectivally modified. 'Equipment', however, is not one of them, and so your teacher's correction was appropriate.

Only a good learners' dictionary can provide reliable guidance on this tricky topic!