TOOL USED WITH RE168250001 AND AIR OPERATED HAND DRILL; MATERIAL CUT-ALUMINUM 2124-T851; TOOL FUNCTION-TO REAM 4TH PASS IN 68A250104 BULKHEAD ASSEMBLY FOR FINAL HOLE SIZE OF .5625 DIAMETER. PREVIOUS HOLE SIZE WAS .5469 KIAMETER PRODUCED BY SPT-RE168250001-510TD