The N20 6V 50RPM Micro Metal Gear Motor with Encoder is designed for 6V operation but can run within a 3V to 6V range, with rotation starting as low as 0.5V. While lower voltages may be less efficient, higher voltages could shorten the motor's lifespan.
These motors are available in various gear ratios, from 5:1 to 1000:1. Except for the 1000:1 version, all models share the same physical dimensions, allowing easy swapping to meet changing design needs.