24 Thread Spline & M3 thread.Suitable for 3 Inch . Specifications24TThread: M3Material: CNC AluminumMiddle hole inner diameter: approx. 2.6mmBigger 4 holes inner diameter: approx. 4mmMaximum Thickness: approx. 5mmMinimum Thickness: approx. 2.5mmMaximum Width: approx. 13mmBody Width: approx. 8mmTotal Length: approx. 84mmDistance from hole center to hole center：3 inchColor: Blue Package Content:1pc x Aluminum Servo Arm.
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