concrete nail Material:C1045,C1055 Length:1"-6" Shank:smooth,grooved,spiral,twisted Diameter:1.0mm-6.0mm COUNTERSUNK HEAD CONCRETE NAILRaw materialC1045 , ... C1050 , C1055…Hardness45 – 55 degreeDiameter2.0mm—6.0mmLength1”—7”ShankSmooth shank & Twisted shank &Bamboo shankSurfaceZinc plated(electro galvanized ... 200pc/box,500pc/box and so on Countersunk head concrete nail