Hexagon head screws with flange and ribs as per pictures in attachment Steel 12.9 with manufacturer mark and production date (month+year) M12x1,5x40/34 thread Key 17mm / Flange 25mm / Head height 8mm Coating: zinc phosphate or burnished With thread locking (yellow) 4-15mm Screws are used in the construction of vehicles 5200 pcs. or minimum order quantity