Product Description For superior quality and color3:1 Ratio epoxy system proven successful in reactive resin, urethane, and polyester bowling ballsBecause it has excellent adhesion and virtually no post-cure shrinkage, there are no issues with flat spots or separation.Very clear and easy to color matchNo air bubbles as it easily allows trapped air to escape.Drills straight and true without bit chatter or chipping.Compound only – Requires Motiv HD or HR Hardner