From Gas Pro:

This is our most successful Gas Pro Spin Vane!

It’s not easy to win an Olympic or Paralympic medal, but we did it!  We introduced our revolutionary Gas Pro 2.5” Target Efficient Spin Vanes just in time for the London 2012 Games and the shooters took full advantage!  With a low profile, long length vane, we provided the shooters with maximum stability while reducing the arrow’s wind drift downrange.  The 2.5” Target Efficient is lightweight, extremely fast and can provide arrow stability to even those with the most demanding draw lengths and weights.  We suggest this vane to be used with small diameter shafts at Target, Field or 3D disciplines.  Enjoy the 2.5” Target Efficient for fast speeds and tight groupings in all situations!