We work with: High-carbon steel (Grade 65Mn/70Mn) – most common for industrial use Stainless steel (301/302/304/316) – corrosion resistance Alloy steel (50CrV/55CrSi/60Si2Mn) – high-temperature resistance Custom materials (available upon request)

Extension springs—defined by their tightly coiled wire structure and looped ends—excel at absorbing and storing energy when stretched, then generating controlled pulling force to return to their original length. This unique functionality makes them indispensable for applications requiring consistent tension, from automotive door latches and industrial machinery to medical devices and consumer electronics.

Crafted to meet strict industry standards, our extension springs deliver exceptional durability, resisting wear and corrosion even in harsh operating environments. We offer a comprehensive range of in-stock extension springs for immediate delivery, plus custom-engineered solutions tailored to your specific load requirements, material preferences, and dimensional needs. Partner with us for reliable tension solutions that elevate your product performance.

Core Specifications

Wire Diameter: 0.1mm – 20mm
Outer Diameter: 1mm – 60mm
Free Length: 5mm – 300mm
Hook Types: Machine Hooks, Cross Hooks, Side Hooks, Extended Hooks, Custom Hooks
Material: Stainless Steel (304, 316), Carbon Steel (SWC, SWP), Alloy Steel, Brass, Phosphor Bronze
Load Capacity: 0.1N – 10,000N
Surface Treatment: Zinc Plating, Nickel Plating, Chrome Plating, Black Oxide, Passivation
Standards: ISO, DIN 2098, ASTM A227, JIS B2706

Extension Spring Hook Types

Half Loop: Low cost, general purpose
Full Loop: Better strength, widely used
German Center Hook: Best fatigue life, most popular for export
English Side Hook: Space saving, side mounting
Extended Hook: Long arm for thick plate
Offset Hook: Avoid interference, offset installation
Swivel Hook: 360° rotating, heavy duty, anti-twist
Duck Bill Hook: Quick assembly, anti-drop

Applications

Our tension springs are widely used in applications that require reliable pull force and rebound, including:

Automotive: Trunk latches, hood hinges, brake systems, seat adjusters
Hardware: Garage doors, screen doors, toys, tools, fitness equipment
Electronics: Hairdryers, vacuum cleaners, printers, mobile phone components
Medical Equipment: Wheelchairs, stretchers, surgical instruments
Industrial Machinery: Conveyors, lifts, valves, switches

GL Springs Advantages

Precision Hooks: CNC machining ensures hook dimensional accuracy and strong load-bearing capacity
Customizable: Support for special hook designs, load requirements, and material specifications
High Tensile Strength: Advanced wire drawing and heat treatment process enhance material toughness
Quality Assurance: 100% inspection before delivery, including load testing and fatigue testing

Shanghai Guanglei Spring Tension Spring – Double Hook Tension Spring

Shanghai Guanglei Spring Tension Spring – Cone‑Shaped Tension Spring

Shanghai Guanglei Tension Spring – Double Hook Constant Spring

Circular hook tension spring

CUSTOM SPRINGS,FROM CONCEPT TO COMPLETION

We are responsible for all aspects from the design stage to mass production.

Spring Design

We’ll work closely with your team to design a custom spring solution.

Manufacturing

For over 20 years, we’ve produced a large array of custom springs in a variety of materials.

Quality Control

Precision Reliability in Every Spring.

Package & Delivery

On-Time Secure Shipping for Custom Springs.

Brands That Trust Us

Trusted By Over 2000+ Brands

FAQ

Are you a factory or trading company? Where is the company located?

We are a leading manufacturer of high-precision springs with IATF 16949 certification, located in Shanghai.

What materials do you use for springs?

We work with:

High-carbon steel (Grade 65Mn/70Mn) – most common for industrial use
Stainless steel (301/302/304/316) – corrosion resistance
Alloy steel (50CrV/55CrSi/60Si2Mn) – high-temperature resistance
Custom materials (available upon request)

Can you produce non-standard springs?

Yes! We specialize in:

Custom shapes (Conical, Barrel, Double torsion)
Special surface treatments (Electroplating, Powder coating, Electrophoretic coating)
Extreme-condition springs (High temperature / Cryogenic)

Can you match competitor samples?

We offer reverse engineering services:

Send samples (3–5 pcs ideal)
We’ll analyze material & performance
Provide matched prototypes within 7 days

Do you provide free samples?

Existing catalog items (≤5 pcs): you only pay actual shipping cost.
Custom sample service: $50 refundable fee (deducted from future orders).

How long does it take for samples?

Typically 5-7 business days. Depends on your request.

Get custom service now

Please inform us about the quantity and application of your custom springs. Based on this information, we will connect you with a specialized engineer who possesses the expertise to address your specific requirements.