Slat armour is a type of protection for vehicles. Imagine you have a toy car and you want to make it tough so it can't get hurt when it's driving around. Slat armour is like putting a fence around your toy car to keep it safe.
But instead of a fence, slat armour is made up of lots of little metal bars. These bars are put around the outside of a bigger vehicle, like a tank or a truck.
The idea is that the slat armour will stop things like rockets or bombs from exploding right next to the vehicle. When a rocket hits the slat armour, it has to go through all of the little bars first. This makes it less powerful and less likely to hurt the people inside the vehicle.
So just like how a fence can protect your toy car, slat armour can protect bigger vehicles from getting hurt.