Features:

  • Suitable for DIY RC model airplane tractor robot motor
  • Made of high quality steel, strong and durable
  • Hole inner diameter 4mm to 4mm, outer diameter 9mm, height: 23mm
  • Based on International Flange Standard, widely used in model shaft connection
  • Include coupler connectors (2pcs), wrench (1pcs) and fastening screws
Great product! Gets the job done!

Used this for an rc boat drive shaft. Used one as 3mm to 4mm. Drilled the second one out to 4mm to 4mm. Good material. Works great. Good set screws and included Allen key. Spray with some white lithium grease for quieter operation.

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