ORIGINAL: Arthur P
Look at one of the teeth on this gear. That is a spline.
What you want to know about is arrow SPINE.
Calling spine "spline" is one of my pet peeves.
Believe it or not (and I can't believe it

) but Easton doesn't have an arrow selection chart on their website any longer. At least, I can't find it if it's there.
Finally.....heh Best post ever