machine screw 1)outside dia: 1mm to 12mm, length: 3mm to 160mm ... is still widely used in the market now.Remark: DK screw head diameterK: height of headL: thread lengthD: outside diameterInternational ... BRAZIER, FLAT, OVAL, PAN, RPUND, TRUSS, HEX etc.Often used driver type (DRIVER):PHILLIPS, POZIDRIV, SLOTTED, TRIANGLE, SQUARE, HEX, SIX-LOBE, TRI ... .)GB/T4424(H62),SUS201-316,SUS410-430 etc. machine screw