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Home / Assemblies and Fasteners / 20 30 40mm Square Tube Connectors Weld-Free, 25 Galvanized Square Tube Tees, Crosses, Elbows, Fixings, and Fasteners

Attributes

Brand -
Category Standard Parts, Components & Industrial Consumables / Assemblies and Fasteners
Origin -
Material Galvanized Steel
Compatible Tube Sizes 20mm, 30mm, 40mm Square Tubes
Connector Types Included Tees, Crosses, Elbows, End Caps
Total Piece Count 25 Pieces per Pack
Installation Method Weld-Free Bolt Assembly
Finish Zinc Galvanized for Rust Resistance
Fastener Type Included Hex Bolts and Nuts
Load Capacity Suitable for Light to Medium Structural Frames
Application Shelving Units, Workbenches, Garden Frames
Package Weight 1.8 kg

6 reviews

A

Anonymous

Mar 28, 2026

Rating: 4/5

Good value, minor fit issues

Overall a solid product for the price. Most fittings were perfect, but two of the elbows were slightly tight on the 30mm tubes. A little force fixed it though.

A

Anonymous

Mar 19, 2026

Rating: 5/5

Exactly what I needed

Bought this to repair an old rack system. The 40mm fittings matched perfectly. Fast shipping and well-packaged to prevent scratching during transit.

A

Anonymous

Mar 19, 2026

Rating: 4/5

Solid construction

The metal thickness is good, not flimsy at all. I deducted one star because the included bolts are a bit soft, but the connectors themselves are excellent.

A

Anonymous

Mar 11, 2026

Rating: 5/5

Great for DIY projects

I am not a professional builder, but these made me feel like one. Clear instructions would be nice, but the design is intuitive enough to figure out.

A

Anonymous

Mar 06, 2026

Rating: 5/5

Perfect for my workshop shelving

These connectors made building custom shelves incredibly easy. No welding needed, just bolt them together. The galvanized finish looks great and feels durable.

A

Anonymous

Mar 01, 2026

Rating: 5/5

Sturdy and versatile

Used these to build a frame for a greenhouse. They hold up well against wind and the weather. The variety of connectors in one pack is very convenient.

5 FAQ

Q: Are the bolts included stainless steel?

A: The included bolts are zinc-plated steel to match the galvanized finish of the connectors. For high-corrosion environments, we recommend upgrading to stainless steel hardware separately.

Q: Can I mix different tube sizes in one structure?

A: Absolutely. Since the pack includes fittings for 20, 30, and 40mm tubes, you can design structures that transition between different tube sizes using the appropriate connectors.

Q: Is there a weight limit for a shelf built with these?

A: The load capacity depends on the tube thickness and span length. For standard 1.5mm thick tubes with short spans, these can support significant weight, but we advise testing gradually for heavy loads.

Q: Do these fittings work with aluminum square tubes?

A: Yes, they are designed to fit standard 20, 30, and 40mm square tubes regardless of material, as long as the outer dimensions match.

Q: What tools do I need for assembly?

A: You will typically need a wrench or socket set to tighten the nuts and bolts. A rubber mallet may help tap the tubes into the fittings snugly before tightening.

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