Custom SUS304 Double Hook Extension Spring Dual Round Loop Ends Tension Pull

Product Description

Our custom SUS304 stainless steel double hook extension spring, also named both ends hook tension spring, is precision‑fabricated by fully‑automatic coiling machines. The spring features a coiled main body with hand‑formed round loop hooks on two terminals. After coiling, parts go through deburring, stress‑relieving tempering and ultrasonic cleaning, retaining natural stainless steel surface without plating treatment. As a durable mechanical reset pull spring, it delivers stable tensile force under repeated stretch‑return cycles. As a reliable manufacturer, we offer flexible OEM and custom service to adjust wire diameter, outer diameter, free length and hook shape according to your technical drawings or physical samples for different industrial assembly requirements.

Technical Specifications

Product Type:Double Hook Extension Spring / Dual Loop End Tension Spring

Raw Material:SUS304 Stainless Steel Spring Wire

Wire Diameter:0.35 mm

Coil Diameter:3.4 mm

Free Overall Length:14.2 mm

End Style:Dual Round Loop Hooks on Both Ends

Surface Finish:Natural Stainless Steel, No Electroplating

Manufacturing Process:Automatic spring coiling → hook bending → deburring → stress‑relief tempering → cleaning

Dimensional Tolerance:Strict ±0.05‑0.1mm precision control for critical dimensions

Applications

Our custom SUS304 extension spring works widely for small‑size mechanical reset structures, household appliances, office equipment, automation accessories, electronic devices, toy assemblies, medical small‑mechanism parts, and precision instrument components that need stable restoring tension force during cyclic operation.

Custom & OEM Service

As a professional spring manufacturer, we provide full custom service and OEM support for stainless steel double hook extension springs. You can send us your 2D/3D drawings or real product samples. We are able to customize wire size, spring OD, free length, loop shape, tensile force and surface treatment. Our engineering team will review your requirement and offer professional technical proposal for your custom SUS304 extension spring project. Small‑batch prototype orders and mass production are both acceptable.

Key Advantages

• Consistent tensile performance to avoid unstable reset force after long‑time repeated stretching.
• Precise dimensional tolerance, ensuring smooth installation without assembly mismatch issues.
• SUS304 raw material provides good corrosion resistance for humid or mild chemical working environments.
• Stress‑relief tempering treatment reduces permanent deformation and prolongs service life.
• Flexible custom service solves the difficulty of sourcing non‑standard special‑size dual loop end tension springs.

Quality Control

We implement full‑range quality control for each batch of custom SUS304 extension springs. Raw material certification inspection is carried out before production. In‑line dimensional measurement checks wire diameter, outer diameter and free length during manufacturing. Finished products will undergo tensile force testing, surface defect inspection and sampling verification. We keep production inspection records to guarantee stable quality for every mechanical reset pull spring we deliver.

Shipping & Delivery

Sample orders of stainless steel double hook extension spring can be finished within 3‑7 working days. Mass production lead time depends on custom specifications and order quantity. Multiple shipping options are available including express courier, air freight and sea freight. Our team will confirm the most cost‑effective delivery solution for your OEM custom service order after production completion.

Frequently Asked Questions

1. Can you make custom‑size dual loop end tension springs besides this standard dimension?

Yes, we are a professional manufacturer offering full custom service. Send us drawings or samples for quotation.

2. Is the SUS304 extension spring anti‑rust for damp working conditions?

SUS304 stainless steel provides good corrosion resistance for general humid indoor and mild outdoor environments.

3. Do you support small‑batch prototype orders?

We accept both low‑volume prototype runs and large‑volume mass OEM production.

4. What files should I provide for custom spring quotation?

2D technical drawings with full dimension data or your original physical samples are acceptable.

5. What is the surface condition of this both ends hook tension spring?

It keeps natural stainless steel finish without electroplating after cleaning and tempering treatment.