"FRAGILITY FACTOR:MODERATELY RUGGED; A KIT CONSISTING OF A ""U"" SHAPED MAGNETIC TOOL AND MAGNETIC RESPONSE MEDIUM. IT IS COMPLETELY PORTABLE. IT IS USED FOR INSPECTION OF FERROUS MATERIAL BY MAKING CONTACT WITH THE MATERIAL AND IMPARTING A MAGNETIC FIELD TO IT. A CONTRAST MEDIUM,RESPONSIVE TO THE MAGNETIC FIELD,IS DUSTED ON THE TEST SURFACE TO DETERMINE WHETHER HIDDEN CRACKS,BREAKS,SPLITS,AIR BELLS OR ANOMALIES ARE PRESENT IN THE MATERIAL SUBJECTED TO INSPECTION. OCCULT IRREGULARITIES,IF ANY,ASSUME A PATTERN AND,IN SOME CASES,THE DEGREE OF SEVERITY MAY BE ESTIMATED"