The 'S' stands for 'stitching' - as in contrast stitching - which is what you get with the 104S. The same great snapback trucker that you're used to, now with a little extra. <br> <br><p><span class=&quot;ASGDescContAttr&quot;>KEY FEATURES:</span> Snapback | Pro-stitched finish | Contrast stitching</p>