Hi Jake,
The self tacking jibs became standard on all SC products in 1992. The self tacking jibs are smaller in area than the old manual tacking jibs. The self tackers are longer in luff length but shorter in foot measurement relative to the old manual tacking jibs. On the SC20 self tacker the jib luff is 2ft longer than the old standard jib and the foot is about 2.5ft shorter. The jib sheeting point for the self tacker is on the front of the front beam and the manual tacker jib sheeting point was 3ft aft of the front beam on the tramp track. The self tacker jibs on all SC products, 15,17,19,20 are all smaller in area than the old standard tacker jibs on the same boat.
Bill