From Lexicanum

Needler weapons are used by some sniper and assassin units of the Imperium. Needlers fire a needle of crystallized toxin. The weapons also make use of a form of laser technology in order to propel the toxic sliver, and to penetrate any existing armour. Needlers are silent and the sliver itself is so fine that it is not felt even if it penetrates flesh. The crystallized toxin dissolves almost immediately after penetration. The toxin is extremely fast-acting, taking effect in a matter of a few seconds.

The laser used by the Needler is invisible and flashless, allowing the weapon to be used without giving away the firer's position. The beam which propels the sliver gives the Needler unerring accuracy, driving the toxin to its target. The secondary function of the beam is to pierce any existing armour and provide an opening for the sliver to penetrate.

Various types of toxins can be employed by the Needler, the most common three being neuro-toxins which are deadly, sedatives which put the victim in a temporary coma, and intoxicants which stupefies the victim, putting him in a completely passive state.

The Needler's main drawback is its poor armour penetration.

The three forms of Needler weapons consist of:

• Needle sniper rifle, the rifle sized and more accurate form of Needler weapon. The needle sniper rifle was a first and second edition weapon used by Space Marine Scouts, Eldar Rangers and Ratling Snipers.
• Needle pistol, a small and elegant version, it is easily concealable and highly favoured by assassins. Silent, flashless and concealable, it is ideal for all kinds of underhanded and secretive work such as assassination, doping and kidnapping. Individuals discovered to be carrying these weapons are regarded with suspicion.
• Needler digital weapon, the miniaturised form of the weapon.

Related articles

• Sniper rifle

Sources

• Warhammer 40,000: Wargear (for second edition)
• Confrontation
• Warhammer 40,000: Rogue Trader, p. 78