They will let you put a little bit of a helical on the arrow, but not much at all becuase they are 2 inches long and are pretty stiff. With the blazers, just put as much of a helical on them as you possibly can while making sure that the vane stays in full contact with the shaft. A while back, I went from shooting straight blazers vanes to helical blazer vanes and I noticed a big difference in arrow flight, stability and groupings. Just my two cents...