JR, I believe its the same as the "100/50". That's what they called it when I ordered my Stepsteel runners. Random sharpening website quote:
How does the hollow play into the choice of profile?
dkmiller,
I had a hip scope about 5 years ago, which didn't help much. Been to many docs and had diagnoses that include mild hip osteoarthritis, FAI, sports hernia, and nerve entrapment (scar tissue).