Options:

F1 - Inf.Health - Read notice 1
F2 - Inf.Ammo
F3 - Inf.Grenades
F4 - Better Accuracy
F5 - Inf.Vehicles Health - Read notice 2

Notice:

Inf.Health will protect you and you only from enemy fire but it wont protect you from grenades so always keep space from your enemy, I did manage to make it protect from grenades but it was effecting the enemy units so i took it out
You should activate it then hover over a vehicle then deactivate it, If you hover over an enemy vehicle while cheat is activate it will reset it health.