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Home / Connectors and Fasteners / Square Tube Connector Fittings, Weld-Free Cast Iron Square Steel Joint Fastening Clips for 20/25/30/40 Guardrail Joints

Attributes

Brand -
Category Industrial Small Parts / Connectors and Fasteners
Origin -
Material Cast Iron
Surface Finish Hot-Dip Galvanized
Compatible Tube Size 20 / 25 / 30 / 40 mm
Connection Type Clamp-On
Welding Required No
Screw Material Hardened Steel
Package Quantity 10 Pieces
Total Weight 2.8 kg
Usage Guardrails, Handrails, Frames
Warranty 1 Year Limited

5 reviews

A

Anonymous

Mar 17, 2026

Rating: 3/5

Screw quality varies

The connectors are fine, but one of the set screws was stripped out of the box. Spare worked though.

A

Anonymous

Mar 12, 2026

Rating: 5/5

Easy installation

Saved me a lot of time not having to weld. The clamp mechanism is tight and secure.

A

Anonymous

Mar 03, 2026

Rating: 5/5

Perfect for 30mm tubes

Fit my 30mm square tubing perfectly. Galvanized finish looks great for outdoor use.

A

Anonymous

Feb 21, 2026

Rating: 5/5

Excellent quality fittings

These connectors are very solid. Used them for a garage guardrail and they hold firmly without welding.

A

Anonymous

Feb 20, 2026

Rating: 4/5

Good but heavy

They work well and are sturdy. Just be aware they are quite heavy compared to aluminum options.

5 FAQ

Q: Are set screws included?

A: Yes, each connector comes with the necessary set screws for installation.

Q: Can I use this for structural support?

A: They are suitable for guardrails and handrails. For major structural loads, please consult an engineer.

Q: What tool is needed for installation?

A: You will typically need a hex key or wrench to tighten the set screws on the clamp.

Q: Does this fit 25mm rectangular tube?

A: Yes, these fittings are designed to accommodate 20, 25, 30, and 40 mm square or rectangular tubes.

Q: Are these rust resistant?

A: Yes, they feature a galvanized finish which provides high corrosion resistance for outdoor environments.

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