Quick Release pins - Technical Information
Single Action and Double Action PinsThis term refers to the method by which
the balls are released to allow the quick release pin to be inserted or retracted. In the case
of a single action pin, there is normally a push button, which when depressed,
allows the balls to retract into the body and the pin moved.
With a double action pin, there is normally a ring, this can be pushed in or
pulled out, to allow the balls to retract and the pin moved. This double action
allows for rapid removal as it can be done one movement.

