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Home / Assemblies and Fasteners / 20/25/30 Galvanized Square Tube Connector Weld-Free Fastener Square Pass-through Aluminum Alloy Joint Guardrail Easy Installation

Attributes

Brand -
Category Standard Parts, Components & Industrial Consumables / Assemblies and Fasteners
Origin -
Material Galvanized Steel and Aluminum Alloy
Compatible Tube Sizes 20mm, 25mm, 30mm Square Tubes
Connection Type Weld-Free Pass-Through Joint
Surface Finish Hot-Dip Galvanized for Rust Resistance
Installation Method Bolted Fastener System (No Welding Required)
Load Capacity Suitable for Standard Guardrail Applications
Package Contents Connector Joints, Bolts, Nuts, and Washers
Application Area Fencing, Guardrails, Shelving Frames, Greenhouses
Corrosion Rating High Durability in Outdoor Environments
Assembly Time Rapid Installation with Basic Hand Tools

6 reviews

A

Anonymous

Mar 28, 2026

Rating: 5/5

Perfect for my backyard fence project

These connectors made building my garden fence incredibly easy. No need to hire a welder, and the galvanized finish looks great. The fit on the 25mm tubes was snug and secure.

A

Anonymous

Mar 14, 2026

Rating: 4/5

Good value for money

Bought the mixed pack for various tube sizes. The 20mm and 30mm connectors worked perfectly. Just make sure your tubes are truly square, as slightly rounded tubes might not slide in as easily.

A

Anonymous

Mar 12, 2026

Rating: 5/5

Great time saver

I used these for a commercial shelving unit. The weld-free design saved me hours of work. The bolts tightened down firmly, and there is no wobble in the structure.

A

Anonymous

Mar 11, 2026

Rating: 5/5

Professional results at home

As a hobbyist, I was worried about structural integrity without welding. These joints are surprisingly robust. My railing feels completely safe and stable.

A

Anonymous

Mar 10, 2026

Rating: 4/5

Sturdy but instructions could be clearer

The quality of the metal is excellent and feels very strong once assembled. I deducted one star because the diagram on the box was a bit small, but overall a solid product for DIY guardrails.

A

Anonymous

Mar 06, 2026

Rating: 5/5

Excellent corrosion resistance

Installed these near the coast where salt air is an issue. After six months, there is absolutely no sign of rust. The galvanization seems to be high quality.

5 FAQ

Q: Can these be used for load-bearing structures like a deck?

A: While strong, these are primarily intended for guardrails, fencing, and light framing. For primary load-bearing deck supports, please consult a structural engineer to ensure compliance with local building codes.

Q: Do these connectors work with round tubes?

A: No, these are specifically designed for square tubes only. Using them with round tubes will not provide a secure connection.

Q: Is the galvanization thick enough for coastal areas?

A: Yes, our hot-dip galvanized finish provides superior protection against salt spray and humidity, making it suitable for coastal environments.

Q: Are the bolts included stainless steel?

A: The included bolts are galvanized to match the connectors. If you require stainless steel bolts for extreme conditions, they can be purchased separately with the same thread pitch.

Q: What size wrench do I need for installation?

A: Standard metric wrenches or socket sets usually work best. The specific size depends on the bolt head included in your package, typically ranging from 10mm to 13mm.

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