Located about 4 minutes from QBP HQ here in Minneapolis is Wolf Tooth. They cut their teeth on making narrow wide chain ring options very early in the SRAM 1 x 11 game and their two latest offerings keep in that vein: Eliptical wide narrow (called "Drop Stop") chainrings for better pedaling ergonomics and stainless steel Drop-Stop chainrings for increased durability. They also have nice anodyzed headset spacers. What we see here are (clockwise, top left): 28T SRAM Direct Mount 426 stainless Drop Stop chainring, an elliptical alloy 30T Drop-Stop Race Face compatible direct mount (Cinch) chainring, an XT compatible 34T Drop-Stop alloy 96 BCD chainring, and an anodyzed blue 32T 104 BCD Drop-Stop elliptical ring. Why Elliptical? Reutedly, elliptical rings deliver a smoother cadence for more reliable power transfer.