DIN 25201 Fasteners for the railway sector Zinc-plated steel M10 (10.7 x 16.6 ), 1000 pcs. M20 ( 21.4 x 30.7 ), 500 pcs. M24 ( 25.3 x 39.0 ), 500 pcs. Stainless steel M8 ( 8,7 x 13,5 ), 1000 pcs. M12 ( 13.0 x 19.5 ), 500 pcs. M16 ( 17.0 x 25.4 ), 500 pcs. M30 ( 31.4 x 47.0 ), 100 pcs.