"True"/"working" sideplates are found on "Sweet Elsies", LeFever's, and other sidelock guns. In a sidelock the hammer, spring, and sear are attached to the plate vice the receiver. LeFevers while not a "true" sidelock as only the cocking indicator is part of the plate generally are classed as sidelocks. The false plates serve not real function except to provide more "canvas" for folks like Ken Hurst. Best, BILL