I made these for Tim Elsner's 6'10" Simm-21 that I just finished shaping. The Simms come standard with a fin set done in laminated exotic hardwoods. Tim wanted something lighter in color and a bit more low-key, so he requested classic marine ply. Tim has requested a subtle wood burn motif on these. I don't know yet what the motif will be, but as Danny Partch has proved, Marine ply keels are a great place for it and they will undoubtedly be very cool.
BTW, my friend Danny and I have always shared inspiration and how-to tips in our fin making businesses. Check Daniel out at http://surfdesignsbydaniel.blogspot.com/