Our 60mm Gearboxes come in a range of ratios. Single stage length up to 10:1 ratio, Double stage length up to 50:1 ratio. Our Gearboxes fit perfectly with our Servo Motors and Stepper Motors out of the box. Need a gearbox for a different motor? We've got a plate for that! Send us an email at firstname.lastname@example.org to get started on your custom gearbox.