5KU Aluminum Enhanced Trigger Housing for Action Army AAP-01 ( ABAAP-023 )

This trigger case make more robust and precious fitting on your upper receiver. Replacing this part set isnt a big deal. It makes more stable and precious fitting on your upper, all the pistol will be a slightly accurate and feels like a bit more robust. Wooble of upper receiver is much better. The only problem with this set the safety will be much stronger. Make active safe needs a strong push-in and push-out, after time it will be lighter and easier.

For this price I am highly recommend this part set if you want a little bit more. Anyways, the original set is clearly good.