VEXpro 20 DP Aluminium Ball Shifter Spur Gears with Bushing - VEXpro 217-3219, Spur gears with cutouts for the VEXpro gear shifter.VEXpro offers a wide assortment of gear types, chosen to provide the greatest versatility of gearing options to users. Sizes have been specifically chosen to provide a wide spread of of ratio options useful for FIRST ® Robotics Competition designers. Larger size VEXpro gears are available so designers can accomplish their entire reduction in a single stage, where otherwise they would have had to have used more than one! All VEXpro 20 DP gears have a 14.5° pressure angle, and have the same overall width. This means that it is easy to interchange VEXpro gears in your design to change a ratio without modifying the overall system. VEXpro 217-3219 50t 20 DP Aluminium Ball Shifter Spur Gear with Bushing