Build high-performance frameless motors for robotics and automation.

Mosrac knows every application is different. That’s why we provide fully standard or custom frameless motor solutions based on your needs—such as torque, voltage, size, structure, and materials. From coils and magnets to lead wires, our engineers work with you to design the right motor to fit our exact needs.

Build high-performance frameless motors for robotics and automation.

Mosrac brings your ideas to life—from early prototypes to volume production—with speed, reliability, and consistent quality.

As one of the most comprehensive frameless motor manufacturers, Mosrac knows every application is different. That’s why we provide fully standard or custom frameless motor solutions tailored to your needs, including torque, voltage, size, speed, and materials. From coils & magnets to lead wires, our engineers work with you to design the right motor to fit your exact needs.

15+

Year Experience

Cert.

CE | Rohs | REACH

98%

On-time Delivery

1M+

Units Annual Shipments

ISO

9001:2015 certified

Trusted by
innovative companies

Mosrac Manufacturing Services from Prototyping to Production

At our own factory in Shenzhen, OEMs rely on Mosrac to develop and manufacture motor solutions tailored to their exact device, application, brand, and system needs—from early prototypes to volume production—with speed, reliability, and consistent quality.

Ultra-Compact frameless motor

Introducing U-series frameless inrunner motors in 12, 14, 16, and 19 mm OD for robot fingers, grippers, and other ultra-compact precision motion applications. View all

Frameless Inrunner Motors

Introducing U-series frameless inrunner motors in 25, 38, 60, and 130 mm OD for robot joints, medical, and other compact precision automation applications. View all

Frameless Outrunner Motors

Introducing UE-series frameless outrunner motors in 15 to 109 mm OD for surgical tools, dexterous hands, humanoid limbs, and cobot precision automation applications. View all

Housed Direct Drive Rotary Motors

Mosrac’s housed direct drive rotary torque motors provide compact, high-torque rotary solutions in varied sizes to fully fit diverse industrial and robotic system needs. View all

Inductive Rotary Absolute Encoders

Mosrac inductive encoders deliver compact, high-accuracy absolute position feedback with hollow-shaft, non-contact designs for robotics, motors, and automation. View all

Humanoid Planetary Robot Actuator

Mosrac planetary joint modules integrate motors, gearboxes, encoders, and drives into compact actuators, delivering high torque, precision, efficiency, and reliability. View all

Smart Production Starts Here

Our manufacturing approach integrates advanced technology with dedicated human support, allowing us to tailor each solution to your project’s specific industry requirements, budget, and timeline.

Commercial Off-The-Shelf

Our commercial-off-the-shelf (COTS) motors are built to handle a wide range of demanding applications. The lineup includes more than 100 standard motors, ranging from frameless inrunner BLDC motors in our U-series to outrunner BLDC motors in our UE-series. Datasheets are available for each model, and typical lead times are about 4-6 weeks.

Modified Off-The-Shelf

MOTS (“modified-off-the-shelf”) motors share the same frameless mechanical design as COTS motors, but use a custom winding. This winding sets the motor’s V (rpm/V), allowing you to tailor it to your application. Mosrac’s engineering team offers electrical design process, including a full study with datasheets and performance simulations.

Offer Custom Frameless Motors Service to Meet Your Needs

Fully Custom

If an MOTS solution is not sufficient and significant tailoring is required, an FC (“fully-custom”) solution is the best choice. FC drive solutions are often highly application-specific and adjusted to complex requirements. Examples of customization options include:

  • Define mechanical requirements (torque/speed) to application
  • Identify environmental constraints (temperature, IP rating, etc.)
  • Define power supply (peak & continuous current and voltage)
  • Define the size available for the motor (OD, ID, Length)
  • Design custom housing for frameless stator and rotor

Hot-Selling Products

Find the precision frameless torque motor, inductive encoder, magnetic encoders, reducers and robot joint module for your special application. Mosrac’s products serve global markets based on both customer-specific (ODM) and our own products (OEM), focusing on cutting-edge motion-control technology.

U12 Series 12MM OD Frameless Inrunner Torque Motor

U12 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U14 Series 14MM OD Frameless Inrunner Torque Motor

U14 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U16 Series 16MM OD Frameless Inrunner Torque Motor

U16 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U19 Series 19MM OD Frameless Inrunner Torque Motor

U19 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U25 Series 25MM OD Frameless Inrunner Torque Motor

U25 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U32 Series 32MM OD Frameless Inrunner Torque Motor

U32 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U38 Series 38MM OD Frameless Inrunner Torque Motor

U38 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U43 Series 43MM OD Frameless Inrunner Torque Motor

U43 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U50 Series 50MM OD Frameless Inrunner Torque Motor

U50 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U60 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U68 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U76 Series 76MM OD Frameless Inrunner Torque Motor

U76 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U85 Series 85MM OD Frameless Inrunner Torque Motor

U85 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U94 Series 94MM OD Frameless Inrunner Torque Motor

U94 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U104 Series 104MM OD Frameless Inrunner Torque Motor

U104 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U115 Series 115MM OD Frameless Inrunner Torque Motor

U115 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U130 Series 130MM OD Frameless Inrunner Torque Motor

U130 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U160 Series 160MM OD Frameless Inrunner Torque Motor

U160 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

U200 Series 200MM OD Frameless Inrunner Torque Motor

U200 Series
Frameless Inrunner Torque Motor

Stator OD (mm): 12

Rotor ID (mm): 4.8

DC Voltage (Vdc): 12/24

Rated Torque (Nm): 0.004~0.02

Rated Speed (rpm): 2000~15000

Your Trusted Manufacturing Partner in China.
Global Shipping

Based in China, Mosrac combines in-house production with a strong R&D team to deliver fast, high-quality on-demand manufacturing solutions. As a leading China-based manufacturer, we offer global shipping to North America and Europe in as little as 10–40 days. With English-speaking project engineers and fast response times, we support customers across time zones to keep production running smoothly.

1000+

Customers Worldwide

50+

Countries & Regions Served

200+

Machines Set

factory_solid
16,000+㎡

Factory in Total

How to Work With Us

A straightforward four-step process — from your specs to a custom quote, precision manufacturing, and on-time delivery of tested motors.

Submit your Motor specs

Send us your torque, speed, voltage, size, and mounting requirements, along with any drawings you have.

Get a Quote & Design

Within 24 hours, our engineers deliver an electromagnetic design, sizing recommendation, and a firm quote.

We start manufacturing

Once you approve the quote, production begins, including winding, varnishing, and dynamic balancing.

Your motors ship out

Every unit passes performance testing and final visual & cleaning inspection before it’s packed and shipped.

End-to-End Solutions for New Motor Development

Comprehensive solutions for all your frameless and housed motor needs, from design to delivery.

Project Initiation, Consult & Design

From concept to manufacturable design, we help your brands turn ideas into prototype-ready solutions.

Industrial design

Material and finish plan

Mechanical design

Cost estimation

Start Your Own Project

Prototype & Low-Volume Runs

Our extensive network supports prototyping and low-volume production, delivering fast, accurate manufacturability feedback.

Manufacturing consulting

Testing support

Assembly support

Low-volume production

Start Your Own Project

Mass Production

We help businesses scale by connecting trusted material suppliers and managing production with full transparency.

Supply chain integration

Technical support service

Raw materials procurement

Cost & delivery oversight

Start Your Own Project

Packaging & Delivery

Our team handles both product and packaging manufacturing, so your goods arrive safe and professional.

Packaging design

Packaging management

Sample testing

Packaging execution

Start Your Own Project

Major Industries Served

Tailored manufacturing solutions for demanding sectors.

Mosrac FAQs

Find quick answers about manufacturing, lead times, materials, quality control, and more.
Need more support?
Start a quote or contact us today.

What is minimum order quantity?

Our MOQ varies by motor and customization level. To get an accurate MOQ for your desired product, please contact our sales team. We understand every business is unique, and we strive to accommodate diverse order sizes.

What industries do your motors serve?

Our motors are widely used in robotics, automation, medical equipment, semiconductor manufacturing, printing, packaging, and other industries requiring precise motion control.

Can you produce motors below MOQ?

While we recommend meeting our MOQ to optimize production efficiency, we can consider smaller orders on a case-by-case basis. For samples or small quantities, please contact our sales team for personalized assistance.

Do you offer motor customization?

Yes, we excel in custom motor design and manufacturing. Our engineers can work closely with you to develop a motor tailored to your specific requirements.

How long is your production time?

Production time typically ranges from 15 to 45 business days but can vary based on product complexity and order volume. For precise estimates and to view product-specific lead times, please visit our product pages.

How do you ensure product quality?

We maintain strict quality control throughout production, including material inspection, assembly testing, and final performance verification. We follow industry standards and certifications to ensure product reliability.

What types of motors do you offer?

We specialize in standard or custom frameless motors, including inrunner & outrunner. It includes a range of torque outputs, sizes, speeds, and currents to meet diverse application needs.

What is your warranty policy?

We provide a standard warranty on our products. Specific warranty terms and conditions may differ based on the motor model and purchase agreement. Please consult our warranty documentation for detailed information.

Can I get a prototype before batch?

Yes, we provide digital proofs for your review and approval before starting production. This ensures that the final product meets your exact specifications.

What is lead time for custom motor?

Lead times vary based on product complexity and order volume. Typically, it ranges from 2 to 6 weeks. For exact timelines, please consult with our sales team.

Still have more questions?

What have I missed?
We cannot wait to hear from you.
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