Small Parts Steel Hex Nut, Plain Finish, Class 10, DIN 934, Metric, M12-1.75 Thread Size, 19 mm Width Across Flats, 10 mm Thick (Pack of 25): Amazon.com: Industrial & Scientific
M12 (12mm) A2 Stainless Steel Hexagon Left Hand Thread Full Nuts Hex Reverse Nut - 2 Pack : Amazon.co.uk: DIY & Tools
Metric Fine Pitch Full Hex Nuts A2 304 Stainless Steel DIN934 – Fixaball Ltd. Fixings and Fasteners UK