When playing a mission, what do the enhancers down the bottom do?

All of the enhancers cost a certain amount of coins, the amount is shown below the icon.

Restore health will restore the health of the unit who you are using at the time back to full health (effective immediately).

Double damage will give the unit you select it on double the hitting power for the next two shots that unit takes in a single mission.

Double max health will give the unit you select it on double the health for the duration of a single mission (effective immediately).

Double armour allows the single unit it is applied on to take no damage in the two turns of that unit following enabling the armour. (To clarify, this means that that unit should be protected from when you enable the armour until the beginning of that unit’s second turn after the turn it was enabled on.)

Accuracy will show you a greater trajectory of each shot before you take it with the unit you use this on for the duration of a single mission.