This high tensile steel action bar is made by precision CNC machines.  It fits Glock 19 (T.Marui) GBB pistol.  It is an enhancement item, which is specially made for professional shooter and competition needs, because:

1) High precision dimension increases shooting reliability and sensitivities;

2) High tensile steel strengths construction, increases durability and reliability;

3) Smooth surface finishing is used to reduce friction inside your GBB Glock and improve smoothness between trigger and sear;

4) Dimension is modified for increasing efficiency and reducing risk of misfire.  Therefore, it has difference dimension from the original T.Marui knocker.