The inner diameter of a regular size Mason jar lid must be between 67.00 mm and 68.00 mm to ensure that it can be securely attached to the mouth of the jar and fit snugly in the standard 70 mm diameter ring. Fifty samples obtained from a certain manufacturing line show consecutive measurements that alternate up and down, as well as a couple of lids with inner diameters that exceed the control limits. This pattern indicates that the process, which results in a Cpk of 0.276 and a Ppk of 0.307, is not stable and not capable.