From abstract: "An instrument for detecting aluminum-silicon alloy penetrations in the aluminum jacket of fuel slugs is described. The instrument is of the eddy current type and the sensing element is a small probe that does not touch the specimen under inspection. Al-Si inclusions 0.020 inch in diameter that penetrate to within 0.005 inch of the can surface can be detected. The response of the circuits is such that a slug 8 inches long can be scanned in 45 seconds."