500-127/16 500-12 Extra Length Aircraft Extension Drill

Aircraft extension-length drill with straight shank, diameter 0.4375" (7/16) with an overall length of 12" and flute length of 4.1/16" according to NAS907 Type B standard with 135° heavy duty split point, HSS with steam tempered finish for 4xD drilling without pecking in steel, stainless steel and cast iron