The "Humility" Class Turret is a Space Pirate copy of the Galactic Federation's Growler Class Turret. The Space Pirates were able to acquire the GF turret, though found the cannon unit inadequate. They replaced the Growler's weapon with a powerful galvanic acclerator cannon, causing it to deal more damage. However, the turret is still fairly slow and can be easily dodged by fast targets. The armor is also fairly weak. Samus Aran encounters these turrets in the Space Pirate's base in Agon Wastes on planet Aether. Samus can easily destroy them by firing a Missile or a Charge Beam shot.
In Metroid Prime 3: Corruption they were outdated by the Remorse-Class Turret.