Innovative Thumb Protractor

Easily determine the "Oval Angle" for any bowler. The Innovative Thumb Protractor is a simple tool to find the oval angle of your customer in very little time. Place the protractor on the thumb hole with the 90 degree line on the center line, ask the bowler to lift the ball up while they only have half of their thumb in the ball and measure the angle on the side of the thumb.