I realize this is a late reply, but I'll give it a shot anyway.
They Retract. The forward part of the Foot Plate, Snaps down to allow your pinky finger to comfortably rest on it. If I hold my Grip normally with the Snap Grip Retracted, my pinky rests under the Mag. If I hold my Grip normally with the Snap Grip Extended, my pinky rests right on the recessed tip of the Snap Grip. This gives me Full-Hands-On when I'm at the Range. Very comfortable and pretty ingenious invention!