When this item is used it generates an electro magnetic pulse that damages everything nearby. In some missions this is a convenient way of taking out (or at least weakening) a large amount of targets at once. It has a long cooldown after use so in most missions you can only use it once or twice. When you activate it there is a delay of a couple of seconds before it goes off so activate it a bit before you reach the middle of your intended area. Remember that it damages targets in all directions. So if you wanted to clear a minefield for example, activate it slightly before you reach the mid point of the minefield for maximum effect. It can also be very effective when you are close to capital ships or stations with multiple turrets, shield generators etc to target.
You activate your EMP by clicking the last of the icons shown to the right or by pressing the 4 key.
EMP Generator - available at level 45
Improved Electromagnetic Pulse - Available at level 50. Does much greater damage and removed shields from targets. Purchased from daily commendations vendor (100 daily coms - Bind on equip so you can sell it/send it to other characters)