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 stainless steel 304, strong and corrosion resistant. Specification:Material: 304 Stainless SteelFinish: Vibration PolishingThread Size: M5 x 10mmOuter Diameter: 16mm / 0.63"Overall Height: 10mm / 0.39"Thickness( Knurled part): 4mm / 0.16" Package content: 4 x Knurled Thumb Nuts.
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