The AR2078 "target" version of the QB family has been around for awhile and is generally well liked for providing good accuracy, quality, versatility, and value. But one of its more curious and less-liked features has always been its funky "hinged" trigger blade that provides a simulation of a 2-stage trigger, but something that's a far cry from the real McCoy.
The "Trigger Cam" fixes that, by providing an adjustable cam face for the hinged portion of the AR trigger to push against. This provides a high mechanical advantage lever action that causes the 1st stage movement of the blade to do actual useful work by moving the sear to the razor's edge of break in true 2-stage fashion. The resulting improved trigger eliminates creep, while providing a good margin of initial sear engagment and safety.
Here's the new listing - tucked away down at the bottom of the AoA Custom Parts page.