The HK MR 556 trigger is a precision engineered component designed to elevate the performance of your firearm. Mirroring the exceptional qualities of our renowned SSA trigger, this trigger is compatible with both the HK 556 and semi-automatic HK 416 models. Crafted for reliability and smooth operation, it ensures a crisp, clean break with every pull, enhancing accuracy and control. Whether you're in a competitive shooting environment or on a tactical mission, the HK MR 556 trigger delivers consistent performance, making it an indispensable upgrade for serious enthusiasts and professionals alike. Dimensions - standard military specification pin Trigger bow type - M4, curved Weapon platform - HK MR556 (upper receiver only) After installing the MR556 trigger, it is necessary to cock the hammer to engage the safety This differs from the HK trigger system, which allows the selector to be placed on 'safe' with the hammer in the forward position