Product Description:Name:Plastic Worm GearModel: 0.5MMaterial: PlasticOuter diameter: 6mmWorm gear length: 6mm, 7mm, 8mm, 10mmCenter hole: 1.95mm, relevant to 2mm optical shaft or axle.Main applications: gearbox, riding wheel, reducer lever, etc.Used:Do DIY science and small production, product design, mechanical model.Remarks: If you've got particular needs, please contact us, we are able to customise in step with your needs!The records is measured manually, for reference only, please talk over with the genuine object!Package Include:According to your Choose!