Quick and easy Contender frame ID. I am sure most already know this but hope it helps the new Contender owners.

If the pin circled in TOP picture below is present then it is a NON easy open frame.

If the pin circled in MIDDLE picture below is present then it is an easy open frame.

If the Raised Piece circled in BOTTOM picture below is present then it is a G-2 frame.

ADDED Frame production Dates by Serial Numbers lower in thread

Hope this helps
Safe shooting
Doug