HARDWIN FASTENERS PVT. LTD. Mfrs. Of Astm Bolts , Studs , Nuts. Sizes: M10 To M 80 , 1/2" To 31/2" In Grade B6 , B7 , B16 , B8 , B8m-class 1& 2 , 2h , 6 , 8 , 8m Monel , High Tensile & Stainless Steel.