 
The Mastermind Ultra Low RG core features a single density squared-off elliptical inner core. The core is dynamically designed to extend the rotational energy, boosting angular velocity to transfer energy to the pins for increased pin action and higher scores.
Core Type
              Asymmetric
          16 pounds
RG
              2.476
          Diff
              0.052
          MB Diff
              0.015
          15 pounds
RG
              2.488
          Diff
              0.052
          MB Diff
              0.015
          14 pounds
RG
              2.504
          Diff
              0.052
          MB Diff
              0.015
          13 pounds
RG
              2.589
          Diff
              0.043
          MB Diff
              0.011
          12 pounds
RG
              2.612
          Diff
              0.043
          MB Diff
              0.011