Hexagon Full Nuts. Hexagon full nuts. M1.6 x 0.25mm pitch, 3.2mm spanner. A2 Stainless Steel. A2 Stainless Steel Hexagon. M2 x 0.4mm pitch, 4mm spanner. M2.5 x 0.45mm pitch, 5mm spanner. M3 x0.5mm pitch, 5.5mm spanner.
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