300pcs Threaded Insert M2 M2.5 M3 M4 M5 M6 Insert Nut Brass Threaded Bushings Internal Thread Knurled Nuts with Plastic Box for Plastic Parts by Heat or Ultrasonic for 3D Printer Parts. x 5, MM, 3 x 6 x 5, M4 x 4 x 6, M4 x 6 x 6, M4 x 8 x 6, M5 x 6 x 7, M5 x 10 x 7, M6 x 8 x 8, 1/4-20 x 12.7 x 8, 300 sheets in total.
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