Features 1、Transfer the torsion of your servo into a gear train with these MOD 0.8 servo gears. 2、This 20 tooth servo gear is most commonly used to drive the 100 tooth hub gear, spaced 48mm away, in order to create a 5:1 ratio. 3、Using high quality brass material, durable and sturdy, wear resistant, long service life. 4、This gear reduction will increase the torsion at the hub gear to 5x what the servo produces. 5、Professional manufacturing, exquisite workmanship, easy to install and use. Specification Item Type: Servo Gear Material: Brass Product Model: 4305-0025-0020 Product Specifications: 25 Tooth Spline 0.8 Module Pitch Diameter: Approx. 16mm / 0.63in Outer Diameter: Approx. 17.6mm / 0.69in Package List 1 x Gear