Do you provide warehousing and shipping services for large orders?

Yes, we offer stock services for long-term business, allowing you to schedule shipments on an annual or monthly basis.

What payment terms do you accept?

We accept T/T, L/C at sight, DP, PayPal, and Western Union for spring orders.

7 Inch Heavy Duty Trampoline Springs for Adult Trampoline

Name: 7 Inch Heavy Duty Trampoline Springs for Adult Trampoline
Brand: Yueqing Dofo Spring Manufacturing Co., Ltd.
SKU: 947957695

Zhejiang, ChinaYueqing Dofo Spring Manufacturing Co., Ltd.

US$0.20-1.00

10,000 Pieces

Product specifications

Type

Sample price:US$80.00/piece.Request sample

Product profile

Customization

Available

Function

Pressed, Buffer

Material

Steel

Model NO.

DF2101315

Usage

Industrial, Auto, Motorcycle, Home Appliance

Load Type

Extension

Production Process

Cold Roll

Shape

Coil

Product Name

Trampoline Spring

Business Mode

Factory OEM

Material Standard

GB 4357-09 or Equivalent

Wire Range

From Min 0.1mm(0.004inch) to Max 12mm(0.48inch)

Winding Direction

Left and Right

End Type

Different Hooks Available

Surface Treatment

Trivalent Zinc Coating

Coating Thickness

8~10 Micrometer

Testing Method

Random Sample Inspection

Tolerance

GB Standard, Grade II or as Per Your Requirement

Spring Rate Tolerance

+-3%~10%

Aql Level

Aql 1.0

Packing Method

OPP Bags with Blank Carton

Normal Carton Size

23X23X31/Cm with No Mark

Certificate

ISO9001, SGS, RoHS, CE, Ts16949

Transport Package

Carton and Outer Wooden Case

Specification

customized

Trademark

DOFO

Origin

Wenzhou, China

HS Code

7320909000

Production Capacity

1, 000, 000 Pieces Per Month

Key features

Customizable Wire Range: Wire diameter ranges from 0.1mm to 12mm to meet specific application needs.

RoHS Compliant Coatings: Offers various coating options like Trivalent Zinc and Nickel Plating that meet RoHS standards.

OEM/ODM Support: Factory provides full customization from samples, designs, or drawings with engineering assistance.

Fast Standard Delivery: Delivers standard springs within 25 days; complex shapes take 30-40 days.

Sample Charge Refundable: Custom sample charges are refunded upon placement of a formal order.

Multiple Hook Types: Available with various hook ends including machine loop, crossover loop, and threaded inserts.

High Quality Standards: ISO9001, SGS, CE certified with 100% visual and function inspection for finished products.

Flexible Payment Terms: Accepts T/T, L/C at sight, DP, PayPal, and Western Union for convenient transactions.

Company profile

High Repeat Buyers ChoiceIn-stock Capacity100% Finished Products InspectionQuality Assurance

Yueqing Dofo Spring Manufacturing Co., Ltd.

Zhejiang, China

CertifiedBusiness Type: Manufacturer/Factory & Trading Company CertifiedR&D Capacity: ODM Service Available CertifiedCustomization Options: Customization from Samples, Customization from Designs, etc. CertifiedExport Year: 26 Years CertifiedNearest Port: Ningbo PortAverage Response Time: ≤4.27h

AI-Powered supplier vetting

SummaryThe supplier presents itself as a professional technical supplier with 3D design, R&D, ODM, and broad customization capabilities. It reports structured production, testing, packing, quality-control, traceability, corrective-action, and complaint-handling procedures, as well as valid contracts with associated subcontractors and inventory capability. Export experience is stated at 26 years, with self-operated import/export rights and 21%–30% of sales from exports. However, it has no overseas warehouse, showroom, agents, or branches, and reports no offline trade-show participation. Certification holdings are explicitly described in the company profile, but current validity is not independently established. Financial credibility cannot be assessed because the supplied financial fields contain zero values. Customer cases and named customer references are not provided.

Supplier typeThe supplier is explicitly identified as a professional technical supplier and describes a mature structure covering management, design, production, testing, and packing. It also has valid manufacturing contracts with associated subcontractors and self-operated import/export rights, supporting classification as a manufacturing-oriented technical supplier.

CertificationsThe company description states that it obtained ISO9001, TS16949, ISO14001, OHSAS18001, and BV certification. The slice does not provide certificate numbers, validity dates, or verification records, so the assessment is based on the supplier’s stated holdings.

After-Sales capabilityThe supplier reports clear procedures and followed records for corrective and preventive actions and customer complaints, plus quality assurance and material traceability. However, it has no overseas agents or branches, overseas warehouse, or showroom, which limits local service infrastructure.

R&D capabilityThe supplier reports R&D capability, new products in the past year, 3D software design services, and ODM services. It does not have an available SDK and does not provide OEM services for popular brands, but those limitations do not negate the stated product-development capabilities.

Production capacityEvidence includes valid contracts with every associated subcontractor, inventory capability, one-month average lead times in both peak and off-seasons, 20 qualified service-capability suppliers, standardized finished-product inspection instructions, and established production and testing structures. The supplier also reports 26 years of export experience and self-operated import/export rights.

Customization capabilityThe supplier explicitly offers customization from samples, customization from designs, full customization, minor customization, and flexible customization, together with 3D design and ODM services. This indicates broad design-to-production customization coverage.

Product Q&A

Q:Which materials are available and do they meet RoHS certification?

We manufacture springs from Carbon steel, Stainless steel, and Music Wire, all complying with RoHS standards. Wire diameter ranges from 0.001 to 0.075 inches.

Q:Do you support small quantity orders?

Yes, we manufacture both large and small quantity springs based on your demand and will help choose the most effective solution.

Q:Does DOFO spring offer design service or initial assistance?

Our experienced engineers provide initial design assistance to lower costs and offer CAD, 3D, and 2D design layouts as well as prototype development.

Q:What is the typical lead time for custom springs?

Standard springs in our mold range are delivered within 25 days. Complex shapes typically require 30 to 40 days.

Q:Do you charge for custom spring samples?

Sample charges are refundable when you place a formal order. However, additional molds required for samples will be charged separately.