1.Made of carbon steel nickel-plated.2.M8 Thread.3.Suitable for standard 45mmx45mm aluminum profile extrusion slot.4.Easy to be roll into T slot of aluminum profile.5.Could be used together with T screw/hex screw Specification:Product Name: Roll Ball Elastic NutsMain Color: Silver ToneMaterial: Carbon SteelFinish: Nickel PlatedModel: 40s-M4Length: .22mm / 0.87"Width: .13.3mm / 0.52"Thickness: .8.9mm / 0.35"Package Content: 12 x Roll Ball Elastic Nuts.
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