HEAD MARKING SHALL BE RAISED OR DEPRESSED (.O10 MAX) AND ARRANGED AS FOLLOWS:
MARK WITH BASIC PART NUMBER ("NAS" OPTIONAL) EXCEPT MARK ,1120-40 SIZE
WITH "4". ,1380.32 SIZE WITH "6". .1640-32 SIZE WITH "8". THESE SIZES ALSO TO
BE MARKED "V" FOR TITANIUM.
MARK WITH MANUFACTURER'S SYMBOL OR TRADEMARK, GRIP DASH NUMBER,
"L" OR "P" WHEN APPLEABLE (j)AND RECESS NUMBER ENCIRCLED. RECESS
NUMBER TO BE APPROXIMATELY 25% LARGER THAN OTHER NUMBERS.
"L" IDENTIFIES BOLTS WITH OPTIONAL LOCKING ELEMENT.
"P" IDENTIFIES BOLTS WITH PATCH TYPE LOCKING ELEMENT ONLY.
"D" IDENTIFIES BOLTS WITH DRILLED SHANK