This device is small and compact requiring no special putters, batteris or additional equipment of any kind.

It allows you to practice your putting stroke anywhere there is a surface large enough to stand.

If there is an error in your stroke it will highlight it so that you can resolve it.

eg When you miss a put it could be for various reasons

1) The putt was not lined up correctly in the first place.
2) The putter head changed direction during the stroke.
3) The putter was brought across the ball and created spin.

How do you know which of the above is affecting your stroke?