... .9(4). Size: M6-M36(5). Material: Carbon Steel(6). Surface treatment: Black oxidePhotos for detail Photos for Packing Ningbo Zhenhai Hualong ... so onSizeM6-M42 LengthM16-300Type of headSquare,Hex,Flange,Hex socket,T-Head and other you can chooseSurface treatmentBlack Oxide,Zinc ... your sampleRegarding to Nuts Type of NutSquare,Hex,Flange,Hex socket,T-type,Coupling,wheel ,acorn,tapper,and so onRegarding to ...