These custom modified grade 8 machine screws were made using 5/16-18 X 1-1/4 Grade 8 hex head cap screws in grade 8 steel material with zinc/clear finish.  The head of each COTS part was machined to the shape seen here, with the head height at .190" +/-.005" and head diameter at .485" +/-.005".  Single flat .42" section was incorporated at one section per our customer's provided sample piece.  Total of 3,000 pieces were modified on this specific production run and the lead time was approximately 2 weeks from the order receipt.