... Stainless steel 410/304/316 pan/countersunk/flat/hex washer/truss self drilling screwSize: ST2.9 - ST6.3 ,#4-#14Sueface hardness ... : HV>530Core hardness: HV>240Head types: CSK(flat),pan,truss,hex,hex washer,hex flange,oval 1: Product information of ... and so onHead Type & Drive TypeCSK(flat) head,pan head,truss head,hexagon head,round head,oval head cross recessed,combined ...