They are more common on the Lefever A grades and the western Arms guns. But they were put on the nitros as well. They are a simple trigger, but not selectable.

Swapping to double triggers would be straight forward. The trigger plates are the same, or at least similar enoigh to make the interchange easily doable. You jist need the parts for the double teigger guns. If you want to do it and need the parts, contact me. I have everything, and lots of them.

B.Dudley