The two pertinent words are easy enough to understand: 

* suit: thing that covers people or *maybe* animals, like clothes
* armour: surface which by design is hard to penetrate and so protects what's inside.

But the thing that has me feeling uncertain is that google images or whatever of "suit of armor" shows some ridiculous ancient clattery thing which I cannot picture in use on a modern-day battlefield. Can you describe what these men are wearing as a suit of armor?

[![Call of Duty](https://i.stack.imgur.com/Mr5Eh.jpg)](https://i.stack.imgur.com/Mr5Eh.jpg)