Runouts are stamped, except for the last two digits which are etched opposite from matrix. Matrix / Runout: XLP 4627-1F B1 (Side A runout) Matrix / Runout: XLP 4628-1AA 1H (Side B runout) Matrix / Runout: XLP 4629-1K 1A (Side C runout) Matrix / Runout: XLP 4630-1AF 1H (Side D runout) Other: ML 4377 (Side A/D labels) Other: ML 4378 (Side B/C labels)