Size:M24-M30 Material:Carbon Steek and Alloy Steel Finish:BlackOxide,Zinc,Chrome,Galvanized,N Specification:bolt1)Size:M24-M302)Material:Carbon Steek and Alloy Steel3)Finish:BlackOxide,Zinc,Chrome,Galvanized,Nickle,Dacromet,Delta-Tone,Geomet,Ruspert4)Grade:4.8,8.8,10.9,12.9