I have for some time, been in touch by e-mails with a guy in the USA called Edward Fagan, who is the  and owner of TennisGeometrics who sell a product called The Power V Grip.

Apart from owning the company, Ed is also the inventor of the mentioned Power Grip.

But what is it exactly?

Here are a few details from Ed

Design Premise -
I am amazed that with all the thought and effort that goes into tennis technology, no one has seriously addressed the shape and functionality of the racquet handle. The tennis industry has continued to ignore the handle and the powerful affect it has on the ability to teach, learn and play the game. Why do you think so many pros have their handle modified? Ever notice how sharp the bevels are when you get a close up on TV? What happened to the grip the racquet came with? Its gone. The great Rod Laver modified his handle so he could get a better grip .

The shape of the handle could be so much better.
It lacks a distinctive frame of reference for moving your hand on the handle from grip to grip. The only grip a standard handle is truly comfortable with is the Eastern Forehand. Once you stray from the Eastern Forehand there is not a strong frame of reference for finding the other grips. The bevels are too small, especially for the Continental and the Semi-Western. It takes years of practice to learn these grips and get used to making the change from grip to grip. It is such a shame to see good athletes get locked into weak grips and poor wrist positions which limits their potential and enjoyment of the game when you know they could be so much better.

So the Power -V- Grip transforms the handle to a user friendly, ergonomically correct shape for the power tennis that is being played today. It makes all the grips easier to teach, learn, and use. It has been designed to correct the deficiencies inherent in today's racquet handle.

The above photo shows the special Power Grip under a normal overgrip.

To find out more, visit the web site for TennisGeometrics here.