Turrets are a type of mod that increases a portal’s attack rate and hit bonus when it attacks an enemy agent. Only rare turrets are currently available. Each turret you deploy on a portal increases its hit bonus linearly, but the increase to the strike factor for each turret after the first is less effective:
|Mod 1||Mod 2||Mod 3||Mod 4||Hit
Turrets also have a stickiness value of 200,000, making them a bit more resistant to critical hits than rare portal shields.