|5.8.2 Fitting and Refitting|
With an enhancement in your cargo, clicking on its icon will display a tool tip which list the effect the enhancement will have on your ship, a -2% decrease in energy usage for lasers, as one example.
If you wish to install it, with the enhancement selected (by clicking on it), press the Use Item button, which has a wrench icon.
To manage your enhancements (once you have some installed), pressing F7 will toggle the Enhancements window, this window will display all your installed enhancements, and the cumulative effect on your ships. Hovering your mouse over the icons in this window will display the names of installed enhancements.
Because you may only install a maximum of eight enhancements at any one time, per ship, this window can also be used to remove enhancements. Left click on an enhancement's icon, the window will change to show just that enhancement and its effect, and also display a Remove button, pressing this button twice will remove that enhancement, permanently.
There's a handy table of the current enhancements in Tactics & New Players » » Unofficial Player's Guide to Enhancements