M2/M2.5/M3/M4-M30 HEXAGON HALF LOCK NUTS A2 STAINLESS STEEL HEX THIN NUT DIN 439. Type: Hexagon Half Lock Nuts. Material: A2 Stainless steel. Features: The product is made of 304 stainless steel with good corrosion resistance, oxidation resistance, heat resistance, high strength and high toughness.
eBay