Threaded Rod Connection Profile – PF-ZN and PF-A4

Flat steel connection plate with a central nut for fixing an M8 / M10 threaded rod to block, panel, plasterboard, brick and lightweight concrete — available in galvanized steel (PF-ZN) and AISI 316 stainless steel (PF-A4).

Grade A steel — C1 galvanizedA4 stainless — AISI 316M8 / M10Max load 100 kg per pointFor weak base materialPlate 69 × 19 mm

Technical specification

Property	PF-ZN / PF-A4 — threaded rod connection profile
Function	Profile for connecting a threaded rod to a ceiling or wall using two anchors
Material	Galvanized steel (PF-ZN) or A4 / SS316 stainless steel (PF-A4)
Supported threaded rod	M8 / M10
Plate dimensions	69 ± 0.5 mm length × 19 ± 0.1 mm width × 2.3 ± 0.1 mm thickness
Anchor holes	Two R26 holes, 9.5 ± 0.1 mm centre-to-centre
Central nut height	6.5 ± 0.1 mm
Recommended maximum load	100 kg per point
PF-ZN part numbers	PFZNM0800 · PFZNM0810 · PFZNM1000
PF-A4 part numbers	PFA4M0800 · PFA4M0810 · PFA4M1000
Engineering design	Method C per EN 1992-4 for engineered projects

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PF-ZN / PF-A4 — Technical Data

Threaded rod connection profile: the complete guide

When you need to connect a threaded rod to a wall or ceiling — whether for suspension, bracing, fixing industrial shelving or a construction project — the classic problem is achieving a reliable connection in base materials that are not cast concrete: blocks, autoclaved (lightweight) panels, reinforced plasterboard, brick and even lightweight concrete. Adit’s solution is the threaded rod connection profile from the PF series — a flat steel plate with a central nut that provides a wide load-bearing base and distributes the force over a far larger area than an ordinary nut.

The series includes two main models: PF-ZN in galvanized steel for interior use and general fixing, and PF-A4 in AISI 316 stainless steel for humid, marine and corrosive environments. Both models are available in three connection sizes and allow a recommended maximum load of 100 kg per point. The flat plate (69 × 19 mm) spreads the pull-out force across two anchor points spaced 9.5 ± 0.1 mm centre-to-centre, dramatically reducing the point pressure on the material — enabling a stable connection even in block and lightweight panel.

Two models – same geometry, different material

PF-ZN and PF-A4 are completely identical in dimensions and connection mechanics. The only difference is the material: the former is made of grade A (carbon) steel with a zinc plating, while the latter is made of A4 stainless steel (AISI 316). The choice between them depends on the environmental conditions.

PF-ZN – Galvanized steel

Material: grade A steel, zinc plated (C1)
Suitable for dry interior environments
Moderate resistance to humid air
Lower cost — suitable for large projects
Available in three codes: PFZNM0800, PFZNM0810, PFZNM1000

PF-A4 – AISI 316 stainless steel

Material: A4 stainless steel INOX C4 (AISI 316)
Suitable for humid, marine and corrosive environments
Maximum resistance to rust and oxidation
Required for projects with a stainless steel specification
Available in three codes: PFA4M0800, PFA4M0810, PFA4M1000

Rule of thumb for choosing the material: if the project is in an outdoor environment, near the sea (up to 5 km), in humid rooms (showers, industrial kitchens) or the contractor’s specification requires stainless steel — choose PF-A4. For all other cases — PF-ZN is sufficient and more economical.

Dimensions and part numbers

Each model comes in three variants that allow maximum flexibility in the connection: M8 nut only, M8 nut with an M10 through-hole, and M10 nut only. This allows an M8 or M10 rod to be connected in any required configuration.

PF-ZN part no.	PF-A4 part no.	D1 – primary	D2 – secondary	H – nut height (mm)	H1 – primary thread depth (mm)	H2 – secondary thread depth (mm)
PFZNM0800	PFA4M0800	M8	–	7.5	7.5	–
PFZNM0810	PFA4M0810	M8	M10	17	7	10
PFZNM1000	PFA4M1000	–	M10	9	–	9

Plate dimensions: 69 ± 0.5 mm length × 19 ± 0.1 mm width × 2.3 ± 0.1 mm thickness · Anchor holes: R26 · Distance between anchor holes: 9.5 ± 0.1 mm · Central nut height: 6.5 ± 0.1 mm.

Applications – where is the threaded rod connection profile used?

The threaded rod connection profile from the PF series solves a real and common problem in the industry: how do you connect a threaded rod to base materials that are not cast concrete, without compromising the stability of the connection? The plate acts as a “base anchor” that distributes the force and allows the use of a smaller, less invasive anchor.

Block and thermal-block walls: hollow blocks (black block, Lego block, thermal block) do not hold a single nut reliably. The PF plate spreads the force across two anchor holes and reduces local pressure — a stable 100 kg connection.
Panels and natural stone: lightweight panel, granite, limestone and natural stone can shatter under concentrated pressure. PF-ZN / PF-A4 distribute the pull-out force and enable rod connection in a stone environment without damaging the material.
Reinforced plasterboard walls and panels: in drywall and heavy plasterboard panels the PF plate connects to the metal profile behind the panel, providing a rigid base for a threaded rod for suspension.
Industrial suspension and pipes: fixing pipes, cable trays, plumbing and industrial fasteners to ceilings and walls — PF enables a quick and secure M8 / M10 threaded rod connection.
Humid and marine environments (PF-A4): seaside hotels, pool facilities, ports and piers — PF-A4 in 316 stainless steel withstands salt and humidity and preserves the connection strength for years.
Cladding and facade panels: fixing cladding panels to building facades via an M8 threaded rod — PF allows a flexible, adjustable connection between the cladding layer and the structure.

Typical settings: residential buildings, industrial structures, hotels and resorts, electrical and server rooms, coastal and marine facilities, and renovation projects.

How does the PF threaded rod connection profile work?

The operating principle is simple and elegant: instead of letting the force generated in the threaded rod act on one small point, the PF plate distributes the force between two anchor points located at the two ends of the plate. This creates a non-concentrated lever, and the point pressure on the base material drops to a third or a quarter compared with a single nut.

Drill two anchor points — drill two holes in the base material (block / panel / lightweight concrete) 9.5 mm apart centre-to-centre, matching the two R26 holes of the plate. Use a drill bit sized for the anchor you have chosen.
Anchor the plate to the base material — fix the PF plate through the two R26 holes using screws, plasterboard anchors, plastic anchors or chemical anchors according to the base material. The plate lies flat and sits flush with the surface.
Thread the rod into the central nut — thread the M8 or M10 rod into the central nut of the plate. The nut comes in a height of 7–17 mm (depending on the model) and provides sufficient thread depth for a stable connection. Fit the suspended component onto the rod and tighten.
Load test and approval — for high loads (above 50 kg) it is recommended to perform a pull-out test at every 10–20 anchor points. Recommended maximum load: 100 kg per point. For projects with engineering requirements the design must follow the Method C principle per EN 1992-4.

Do

Use two anchors / screws to fix the plate — never just one
Choose an anchor suited to the specific base material
In humid environments and outdoors — always choose PF-A4 stainless
Make sure the threaded rod engages at least 6 thread turns into the nut
Work within the recommended maximum load: 100 kg per point
For engineered projects — obtain engineer approval

Don’t

Do not fix “by hand” (loosely) — the plate requires two balanced anchors
Do not exceed 100 kg per point without an engineer’s check
Do not use galvanized PF-ZN in a marine or humid environment
Do not hang safety loads (personal fall-arrest anchors) on PF without special approval
Do not thread in a rod that is too short — minimum 6 turns
Do not fix to a rotten, heavily cracked or unstable base material

Choosing the right model – M8 or M10?

Model selection depends on two parameters: the diameter of the threaded rod you will use, and the required connection type — whether the rod enters from below through a hole, from above, or whether two rods of different diameters are needed.

Model	D1 – top nut	D2 – bottom connection	Ideal use
PFZNM0800 / PFA4M0800	M8	–	M8 rod only, direct connection from above
PFZNM0810 / PFA4M0810	M8	M10	M8 rod from above + M10 through-connection from below, maximum flexibility
PFZNM1000 / PFA4M1000	–	M10	M10 rod only, higher loads

For most common applications the M8 model (PFZNM0800 / PFA4M0800) is sufficient and economical. For heavy suspension above 60 kg — prefer M10.

Frequently asked questions

What is a threaded rod connection profile and why is it better than an ordinary nut?

A threaded rod connection profile (Flat Bar for Fixation) is a flat steel plate with a central threaded nut and two anchor holes at its two ends. Its advantages over an ordinary nut: load distribution — the force is split between two anchor points rather than concentrated at a single point; suitable for weak base materials — blocks, lightweight panels and plasterboard where a single nut may grip unreliably; easy installation — the plate lies flat on the surface and provides a stable base; and a high maximum load of 100 kg per point, far higher than a single connection in block.

Is PF-ZN suitable for outdoor use?

PF-ZN comes with a zinc plating (Zinc Plated C1) suitable for dry to humid interior environments. In a dry, protected environment (warehouse, shed) PF-ZN can be suitable for short to medium term. Outdoors without protection, near the sea or in a humid environment, only PF-A4 stainless should be used. Many construction specifications require A4 stainless steel for any external connection — check with the engineer. Note: C1 galvanizing is not sufficient for a marine environment; plating durability is measured in salt-spray hours per ISO 9227, and C1 is not rated for outdoor use.

Which anchor should be used to fix the PF plate to block?

Choosing the anchor for the plate’s R26 holes depends on the base material: for hollow block (black / Lego) use a plastic anchor (plug) size 8 mm + M5 / M6 screw, or an epoxy chemical anchor for block; for thermal block / lightweight concrete use a nylon toggle anchor for hollow holes, or a chemical anchor; for lightweight panel / natural stone use an M6 chemical anchor in an 8 mm drilled hole; for cast concrete use an NA-C Ø6 arrow anchor or a classic M6 mechanical anchor. Contact Adit’s engineers for advice on the correct combination of PF plate + anchor for your base material.

What is the difference between PFZNM0810, PFZNM0800 and PFZNM1000?

All three models are identical in plate dimensions (69 × 19 mm) and anchor holes. The difference is in the central nut geometry: PFZNM0800 (PFA4M0800) — M8 nut only, height 7.5 mm, for an M8 rod from above (the simplest); PFZNM0810 (PFA4M0810) — M8 nut from above with an M10 through-connection from below, height 17 mm, allowing an M10 rod to pass through the plate and an M8 rod above it (maximum flexibility for pipes and profiles); PFZNM1000 (PFA4M1000) — M10 nut only, height 9 mm, for an M10 rod only (higher loads). For most common applications PFZNM0800 is sufficient and economical.

How many threaded rods can be connected to a single PF plate?

Each PF plate contains only one central nut — that is, only one rod connection. If several rod connections are required, several PF plates must be used. The number of plates required depends on the distance between suspension points and on the loads. For a continuous row of connections (for example a cable tray) PF plates can be arranged in a line at equal spacings. Contact Adit for a suitable solution.

Is the PF plate suitable for personal safety anchorage (EN 795)?

No. The PF plate is intended for non-structural connections and general suspension up to 100 kg. It is not approved for use as a personal anchor point for work at height (EN 795). Such use requires a safety anchor approved to the EN 795 standard (such as Adit’s BTeye2), a pull-out test by a certified body, and installation on an approved frame with registration by an engineer.

What thread depth does the PF plate provide?

The available thread depth varies by model (single M8, combined M8/M10, or M10), with the exact H1/H2 values given in the technical datasheet. The recommended minimum thread depth for an M8 rod is 6 turns ≈ 8 mm, so the M8 models at 7–7.5 mm height are borderline — make sure the rod enters as deep as possible and that the nut is tightened per the manufacturer’s instructions.

Can the PF plate be used together with a chemical anchor?

Yes — this is one of the recommended methods. The PF plate is connected to the base material through the R26 holes using an M6 chemical anchor in each hole. This method is especially suitable for hollow blocks and lightweight panels where a single mechanical anchor will not work, for relatively high loads (60–100 kg) requiring maximum grip, and for non-uniform base materials where an arrow anchor cannot expand properly. Chemical anchor + PF plate is a strong, reliable combination even in challenging environments.

What is the difference between PF-ZN and an ordinary base plate?

Both are steel plates that enable a connection, but there are fundamental differences. PF-ZN / PF-A4 is a small, specific plate (69 × 19 mm) with a nut ready for a threaded rod connection — fast to install, low cost, intended for a single anchor point. A base plate is a larger plate, usually with 4 corner anchor holes, for heavy structural connections and engineered projects. PF is the fast, economical solution for single connection points; for heavy structures an engineered base plate is required.

What is the minimum block strength for using the PF plate?

The PF plate does not define a minimum strength for the base material — rather, the anchors that fix it do. As a rule of thumb: solid concrete block (heavy black block) can work at any load up to 100 kg; hollow block requires the anchor to reach the strong inner wall, or a chemical anchor; thermal block / lightweight concrete requires a chemical anchor, maximum load 60–80 kg per point; lightweight panel requires an M6 chemical anchor, maximum load 50–70 kg per point. When in doubt, perform a pull-out test before execution and stop before 80% of failure.

How do you connect a pipe or tray to a block wall with the PF plate?

A common working method: drill two holes in the wall according to the plate hole positions (9.5 mm centre-to-centre); fix the PF plate (PFZNM0810 or PFA4M0810) to the wall with an M6 chemical anchor in each hole; thread an M8 threaded rod from the nut towards the pipe; fit a pipe clamp onto the rod and tighten. The PFZNM0810 model, with D1 = M8 and D2 = M10, allows flexibility — an M10 rod can pass from below and an M8 rod can connect from above to the clamp. Especially efficient for double cable trays.

Is an engineer required to approve use of the PF plate?

It depends on the use. Home suspension / light fixing (shelves, pipes, boxes) — no engineer required, follow the instructions and the maximum load of 100 kg. Fixing to building facades and cladding — an engineer is required to calculate per EN 1992-4 and perform a pull-out test. Critical infrastructure (bridges, energy infrastructure) — an engineer plus certified testing at every point is required. Any use where a falling component could injure people — engineer approval is required. Adit’s engineers are available for consultation and a tailored calculation.

Interested in the PF-ZN / PF-A4 threaded rod connection profile? Adit’s engineers will help you choose the right model and calculate the quantity required for your project.

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