Quark Elsa powermeter. Has always worked flawlessly. I've moved to 150 cranks and very sad I can no longer use this. Reports cadence and power as well as L/R balance.
This is the updated version that does NOT require a magnet.
Carbon 165 crank arms, 130BCD, BB30.
Included are 53/39 SRAM powerglide 10/11 speed chainrings

$700 includes shipping