FEETECH FS90MR 360° Micro Servo 9g – All-Metal Gear Continuous Rotation for Arduino RC Projects

Overview

Meet the FEETECH FS90MR 360° micro servo, a compact 9 g unit designed for continuous rotation. This model is available as a convenient 5-pack with 25 cm cables and a standard JR-type connector, making it easy to equip multiple projects or keep spares on hand for rapid prototyping.

Built for real‑world hobby and educational use, the FS90MR combines a compact footprint with a robust engineering approach. The kit emphasizes a practical approach to learning and building, offering a ready-to-use solution that fits tight spaces on small robots, RC craft, and automated test rigs.

Durable metal gear design

The standout upgrade is an all‑metal gear system featuring precision machined brass gears. This design choice aims to improve wear resistance and torque handling compared with plastic gear alternatives, helping the servo endure higher loads and resist gear stripping over time. A sturdy iron core shaft further reinforces the drive train, contributing to a more resilient overall build for demanding applications.

360° rotation with precise control

Engineered for smooth, continuous 360° rotation, FS90MR responds quickly to PWM commands with a very small dead band. This makes it a practical option for wheel-drive setups, rotating arms, or other continuous-motion tasks in DIY robots and RC platforms. The unit is designed as a drop-in replacement for the FS90R in compatible systems, broadening its potential use across established projects.

• Rotation type: continuous 360° with a tight dead band
• Torque options: 25.04 oz‑in (1.8 kg·cm) at 4.8V; 30.8 oz‑in (2.2 kg·cm) at 6V
• Response: fast, predictable speed changes suitable for drive systems
• Durability: metal gears and iron core shaft for better shock tolerance

Compatibility and applications

The FS90MR uses PWM control and accepts standard JR-type wiring, simplifying integration with popular microcontrollers such as Arduino and Raspberry Pi. Its compact form and 360° capability open up possibilities for 1/8 and 1/10 scale RC models, mini robotic arms, wheel-vehicle prototypes, and automated test rigs.

• Drop-in replacement for FS90R in many setups
• Ideal for hobby robotics, RC vehicles, micro automation, and educational projects

Why choose FEETECH FS90MR

The FS90MR balances a lean 9 g profile with sturdy metal gears and flexible control options, offering a versatile option for experimenting with continuous rotation in tight spaces. While performance can vary with conditions, this servo provides a solid foundation for prototyping and learning across a range of projects.