[66AC]

I believe that the original Cobra seats have seven (7) stitch lines in the seat area and are more fan shaped than the Factory Five seats. The ERA seats are more in line with the originals if that matters to you. The new ERA seats are metal framed and have a rubber trampoline cushion nearly exactly like the 1960's AC seats. Also the ERAs have the wool rear exterior last time I saw them. Of course as you pointed out, there is a bit of a steep price difference between the ERA and Factory Five seats.