The entire Ki-Tech line employs the use of COR testing to ensure quality, consistency and performance. All five grades of hardness are put thru entirely different processing. Most tip manufacturers simply use different amounts of pressure to create hardness grades. Outsville does not. Each grade is engineered and processed to provide the specific feedback and performance expected from each hardness grade.While tips have been solely graded on hardness for years the winds of change are always blowing. Coefficient of Restitution determines the feel and energy transfer of a tip. It’s a measure of elasticity. After years of R&D we have learned to control and increase the amount of COR normally found in leather. The Outsville Ki-Tech Single Layered is the first of several tips to be offered by Outsville to the cue sports market. Single layered means no more delaminations and a greater ability to withstand impacts and remain at the hardness you purchased. Over a decade ago Moori changed the face of billiard tips forever by creating the first layered pigskin tip and it took the market by storm. Mr. Moori knew that the skins of the Japanese Pig was more elastic than either cowhide or water buffalo. By gluing layers of Japanese pigskin together he brought to market a tip that played different than what had came before and tip technology would never be the same again.Tip Details:Diameter: 14 mm