1.A thumb nuts with a knurled outside surface, this facilitates tightening by hand.2.The circular nut with knurled is easy to assemble and disassemble.3.Made of good quality metal material, zinc plated finished, corrosion resistant and durable to use. Specification:Material: MetalFinish: Zinc platedThread Size: M4 x 0.7mmOuter Diameter: 12mm / 0.47"Overall Height: 8mm / 0.31"Thickness( Knurled part): 3.8mm / 0.15"Package content: 10 x Knurled Thumb Nuts.
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