Square tube

The Strofix square tube (40 × 40 × 2 mm) is an AISI 304 stainless-steel square-section tube with 40 mm sides and 2 mm wall thickness, used as a railing post or structural member in balustrade and railing systems with flat-profile designs. Supplied in a single 6000 mm length, satin finish. The tube can be cut to specific sizes on request.

The 40 × 40 mm profile is compatible with Strofix flat-mount crossbar holders, flat-mount blind-hole bar holders, and flat-mount connecting holders, all of which are designed for flat mounting surfaces. The 2 mm wall thickness provides structural rigidity for railing post and framework applications. The tube is supplied as a straight length and is suitable for joining by pasting (adhesive bonding). AISI 304 stainless steel is suitable for standard interior and exterior railing installations.

The satin finish provides a uniform, low-maintenance appearance that reduces visible fingerprints and micro-scratches, consistent with other Strofix railing components in the same finish.

Use cases:

• Railing posts for flat-profile balustrade systems with crossbar or glass infill
• Structural framework tubes for commercial and residential railing designs
• Staircase and balcony railing posts with a square aesthetic
• Perimeter and garden railings with square-section tube construction
• Railing systems using Strofix flat-mount crossbar holders and bar holders

FAQ:

What are the tube dimensions?

The tube has a 40 × 40 mm square cross-section with 2 mm wall thickness (t). These are fixed for this SKU.

What length is available?

This square tube is supplied in 6000 mm (6 m) lengths only. There is no shorter length option in the dropdown. The tube can be cut to specific sizes on request.

Is this tube compatible with Strofix crossbar holders?

Yes. The 40 × 40 mm flat profile is compatible with all Strofix flat-mount crossbar holders, including flat-mount blind-hole bar holders (left and right), flat-mount connecting holders, and flat-mount crossbar holders with selectable crossbar diameters. These flat-mount components are designed to sit flush against flat surfaces such as this square tube.

How is the tube joined?

The product description states the tube is suitable for pasting (adhesive bonding). Select an appropriate stainless-steel adhesive for the specific installation requirements.

What steel grade and finish is used?

The tube is manufactured from AISI 304 stainless steel with a satin finish. AISI 304 is suitable for standard interior and exterior installations.

How does this differ from the Ø42.4 mm round pipe?

The square tube has a 40 × 40 mm flat-sided profile, while the round pipe has a Ø42.4 mm circular cross-section. The square tube works with Strofix flat-mount holders; the round pipe works with Strofix Ø42.4 holders. Choose based on the desired post profile and the matching crossbar holder type.

About Pipes & Bars

Pipes and bars are the stainless-steel raw-stock components used to build handrails, railing infills and structural frames in balustrade systems. Round pipes serve as handrails and post tubes, square tubes form flat-sided posts and handrails, and solid bars function as horizontal rod infills between railing posts.

Strofix supplies three products in this category: a round pipe in AISI 304 stainless steel with a satin finish (3000 mm length), a square tube in AISI 304 with a satin finish (6000 mm length), and solid bars in Ø10 and Ø12 mm diameters in AISI 304 with a raw surface (6000 mm length), with AISI 316 available on the bars.

These are cut-to-length stock items that the installer trims to the required dimensions on site.

The correct product depends on the railing component being built, the required profile shape and the steel grade.