The set includes trigger, trigger spring and D-version hammer spring, enabling you to replace the composite trigger of your pistol with one made of solid steel.
It fits all Beretta full-sized series 90 pistols. Note: it will not fit Billennium, Steel One or Combat models.
Like the smooth feel of the steel vs the textured feel of the poly trigger. The D-spring definitely eased up the DA side of the trigger and the SA also. Easy to install about 20 min.Thanks again Baretta.