Bottom fastening with 2-3 screws (D80)

The Strofix bottom fastening with 2–3 screws (D80) is an AISI 304 stainless-steel round base plate for the Ø42.4 mm railing post tube. The plate has a Ø80 mm diameter (D), 4 mm thickness (h), and is available with either two or three Ø8.5 mm bolt holes (for M8 bolts). Select the number of screws in the dropdown at order time. Supplied with a raw (unfinished) surface. The post tube is attached by welding (elements for welding included).

The Ø80 mm round plate provides a compact circular footprint for the Ø42.4 mm round post tube. The two-bolt and three-bolt options allow the installer to choose the anchor pattern: two bolts for simpler installations with lower loads, three bolts for increased stability with an asymmetric triangular anchor pattern. The Ø8.5 mm bolt holes accept M8 bolts or anchor rods. This is the most compact and economical base plate for the Ø42.4 mm round tube in the Strofix range. AISI 304 stainless steel is suitable for standard interior and exterior installations.

The raw surface finish is standard for base plates concealed by a decorative cover after installation.

Use cases:

• Compact floor mounting of Ø42.4 mm round railing post tubes
• Two-bolt anchor pattern for light-duty residential railing installations
• Three-bolt anchor pattern for improved stability on round post bases
• Budget base plate for Ø42.4 mm round tube railing systems
• Installations where a Ø80 mm circular base footprint is required or preferred

FAQ:

What post tube does this base plate fit?

The base plate fits the Ø42.4 mm round post tube — the standard railing pipe in the Strofix product range.

How many bolt holes are available?

Two options: 2 or 3 bolt holes. Select in the dropdown at order time. Both options use Ø8.5 mm holes for M8 bolts.

What are the plate dimensions?

The plate is Ø80 mm diameter (D) with a 4 mm thickness (h). This is a round plate, not square — matching the circular profile of the Ø42.4 mm post tube.

What bolt size do the holes accept?

The Ø8.5 mm bolt holes provide clearance for M8 bolts or anchor rods.

How does this compare to the D100 round tube base plate?

This product has a compact Ø80 mm plate with 2–3 bolt holes for M8. The D100 base plate (SKU SP-42100) has a larger Ø100 mm plate with 2–4 bolt holes. Choose based on the required footprint size and number of anchor points.

How is the post tube attached?

The post tube is welded to the base plate using TIG or MIG welding.

About Base & Clamp Fastenings

A base or clamp fastening is a stainless-steel plate or bracket that anchors a railing post to the building structure, forming the structural foundation of the balustrade. Bottom fastenings bolt to the top of a floor slab, deck or beam, while side fastenings bolt to the vertical face of a fascia, edge beam or wall. Assembly clamps grip an existing tube or post without welding, and assembly plates provide a flat mounting surface for auxiliary connections.

Strofix supplies 18 base and clamp products for Ø42.4 mm round pipe and 40×40 mm flat-sided square posts, with plate diameters from Ø80 to Ø100 mm (round) and plate dimensions from 80×80 to 135×56 mm (rectangular/square), in satin or raw-surface stainless steel with AISI 304 and AISI 316 options.

Screw-hole configurations include 2, 3 and 4-hole variants. The correct fastening depends on mounting orientation, post profile, plate size, number of screw holes and the required surface finish.