surface treatment:plain,galvanized,black grade:4.8,8.8,10.9 standard:GB,DIN, ... UNITED STATES STANDARD Specifications:1) Color: galvanized, black, plain2) Diameter: M6 - M243) Length: 65mm - 200mm4) Grade: 4.8 ... DIN931 4.8 8.8 10.9 BOLT(zinc plated,black,plain)