Iszy Billiards 6 Dot Measle Pool Cue Training Ball (2 1/4-Inch, White) Go to amazon.com Related posts Top cue ball trainer DescriptionRegulation size 2 1/4-Inch cue ball 6 oz. This is a great training ball to improve your skills. Made of polyester resin which has 6 red spots to visualize the spin of the ball. Instructions are unavailable.