Slots
All weapons in Neocron that are self constructed or mission rewards have the ability to spawn with slots.
Slots are indicated by a series of boxes (ranging from 1-5)on the item's icon.
The maximum slots a weapon can have is 5. The amount of slots that are received is somewhat random. When an item is constructed a roll is made, if the roll is under a certain value, a slot is added. This means that the higher your skill the better the odds of getting more slots, to a certain cap (which is unknown). It also means that if your skill is below a certain threshold, or the quality of the item is too low when made, it cannot have a slot.
Using slots
Slots are used for weapon mods.
Perhaps the most important mods are those that allow a weapon to use additional types of ammo. This is important because all non-standard ammunition deal greater damage than the standard ammunition.
Some mods are used to extend the statistics of the weapon such as damage, frequency, handling and accuracy.
Apart from mods to achieve better weapon statistics, there are also mods that can be used to add functionality like a scope, a flashlight, a silencer or a visible laser beam.