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Home / Assemblies and Fasteners / 20/25/30 Aluminum Alloy Square Tube Connector, Galvanized Steel Pipe Joint, Weld-Free Fastener for Guardrails, Shelves, and Tables

Attributes

Brand -
Category Standard Parts, Components & Industrial Consumables / Assemblies and Fasteners
Origin -
Material Aluminum Alloy & Galvanized Steel
Compatible Tube Sizes 20mm, 25mm, 30mm Square Tubes
Connection Type Weld-Free Bolted Fastener
Surface Finish Silver Anodized / Galvanized
Load Capacity Up to 150 kg per joint (static)
Package Contents Connectors, Bolts, Nuts, and Allen Key
Corrosion Resistance High (Suitable for Indoor/Outdoor)
Installation Tool Required Included Hex Key / Wrench
Application Scenarios Guardrails, Shelving Units, Workbenches, Tables
Country of Origin China

6 reviews

A

Anonymous

Mar 25, 2026

Rating: 5/5

Perfect for my workshop shelves

These connectors made building custom shelving incredibly easy. No welding needed, and they hold the weight of heavy tools without any wobble. The galvanized finish looks great too.

A

Anonymous

Mar 22, 2026

Rating: 4/5

Sturdy but instructions could be better

The quality of the aluminum alloy is excellent and feels very durable. I deducted one star because the assembly diagram was a bit vague, but once figured out, it works perfectly for my balcony guardrail.

A

Anonymous

Mar 21, 2026

Rating: 5/5

Great value for money

I bought the 25mm set for a workbench frame. Everything fit snugly, and the bolts tightened securely. Much cheaper than hiring a welder and just as strong for my needs.

A

Anonymous

Mar 06, 2026

Rating: 5/5

Exceeded expectations

Very impressed with the build quality. The galvanized coating seems robust against rust. I used these for an outdoor railing project, and they have held up well through rain and sun.

A

Anonymous

Mar 02, 2026

Rating: 3/5

Good product, slight sizing issue

The connectors are well-made, but the 30mm version was a tiny bit loose on my specific tubes. I had to use some shims to get a tight fit. Works fine now, but check your tube dimensions carefully.

A

Anonymous

Mar 02, 2026

Rating: 5/5

Ideal for DIY projects

As someone with no welding experience, these fasteners are a lifesaver. I built a sturdy table for my garden in under an hour. The hardware included was sufficient and high quality.

5 FAQ

Q: Is this suitable for outdoor use in rainy climates?

A: Yes, the galvanized steel and aluminum alloy materials provide excellent corrosion resistance, making them suitable for both indoor and outdoor environments.

Q: What is the maximum weight these can support?

A: While dependent on the overall structure design, a single joint is rated for approximately 150 kg of static load. For dynamic loads, we recommend reinforcing the structure.

Q: Can these connectors be used with round pipes?

A: No, these specific connectors are designed exclusively for square tubes with dimensions of 20mm, 25mm, or 30mm. They will not fit round pipes securely.

Q: Can I disassemble and reuse these connectors?

A: Absolutely. Since they are bolted and weld-free, you can easily unscrew them to modify your structure or reuse the components for a new project.

Q: Do I need to buy bolts separately?

A: No, each package comes complete with the necessary high-strength bolts, nuts, and an Allen key for immediate installation.

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