Flat plate fitting · 1-5/8 in. series
P1064 — 1-Hole Flat Plate Fitting, 1/2 in. Bolt
A flat 1-5/8 in. square of steel with a single 9/16 in. hole. It sits on the open face of the channel and spreads one bolt's clamp across the full width of the lips instead of letting the bolt head bear on them directly.
By Alex · Last reviewed 2026-09-25 · Spec looks wrong? Tell us.
- Size
- 1-5/8 in. square (41.3 mm)
- Hole
- 1 × 9/16 in. (14.3 mm) — for a 1/2 in. bolt
- Steel
- About 0.23 in. (5.8 mm) base steel before coating; a hot-dip galvanized part measures thicker; catalog reference part 1/4 in. (6.4 mm)
- Fits
- 1-5/8 in. series strut channel
- Catalog ref.
- Unistrut® GEC no. 17, pp. 85, 90
Dimensions above are the catalog specification for the reference part; the steel line is our supply. Steel grade is confirmed at quotation.
P1064-EG — electro-galvanized, zinc plating to ASTM B633 Type III SC1. Smooth bright silver. Indoor and dry service. P1064-HG — hot-dip galvanized to ASTM A123 or A153. Visible spangle, heavier edge build-up. Outdoor, wet and coastal service. P1064-PL — plain, uncoated steel. For painting or powder coating after assembly, or dry enclosed runs. Stainless — the catalog offers stainless, aluminum and fiberglass on some part numbers but publishes no standard suffix for them and says to consult the factory. Quote as made-to-order. Powder-coated — powder coating to a customer-specified RAL color. Not a catalog finish, so it carries no catalog code — the color, which parts take it and the film build are confirmed at quotation. We publish no film thickness and no salt-spray figure, because we have not measured one.
Finish list: Unistrut® General Engineering Catalog no. 17, p. 85 — finishes note. Powder coating is our option, not a catalog finish. The catalog also lists GR against this series — not quoted, see Finishes.
Pack: Packed per order. The bolt and the channel nut are separate lines — one of each per plate.
Catalog figures for the reference part, with where each one comes from. Our supply thickness is in Supply summary.
| Dimension | Catalog value (reference part) | Source |
|---|---|---|
| Plate size | 1-5/8 in. square (41.3 mm) | Unistrut® General Engineering Catalog no. 17, p. 90 — printed on the part drawing |
| Bolt size | 1/2 in. | Unistrut® General Engineering Catalog no. 17, p. 90 — printed in the part table |
| Hole size | 9/16 in. (14.3 mm) | Unistrut® General Engineering Catalog no. 17, p. 90 — printed in the part table |
| Hole count | 1 | Unistrut® General Engineering Catalog no. 17, p. 90 — printed in the part table |
| Material thickness | 1/4 in. (6.4 mm) | Unistrut® General Engineering Catalog no. 17, p. 90 — standard-dimensions note in the page header |
| Steel | ASTM A575 / A576 / A635 / A36 | Unistrut® General Engineering Catalog no. 17, p. 85 — fittings material note — also meets the physical requirements of A1011 SS GR 33 |
| Hole position | not published | The p. 90 drawing shows the hole centered in the square but does not dimension it, so no center-to-edge figure is published here. |
| Corner radius | not published | Not dimensioned on p. 90. |
| Edge finish | not published | Neither p. 90 nor the p. 85 material note states whether the blank is sheared or punched, so no burr or edge-break condition is stated here. |
Thickness is not a page-wide constant on p. 90. The P1959 / P1960 / P1961 tapped group printed alongside carries its own material note, 3/8 in. (9.5 mm) thick. P1064 takes the 1/4 in. of the page-header standard note, but confirm which group a substitute is copying before you assume it.
The rest of the plate group
P1064 is one line of a six-row table: the same 1-5/8 in. square plate with a different hole in it. The bolt size and the hole size are the only things that change down the table, so a bolt through the hole is the quickest way to tell the six apart if the labels have come off.
| Part | Bolt size | Hole size |
|---|---|---|
| P1062 | 5/16 in. | 11/32 in. |
| P1063 | 3/8 in. | 7/16 in. |
| P1064 | 1/2 in. | 9/16 in. |
| P1964 | 5/8 in. | 11/16 in. |
| P2471 | 3/4 in. | 13/16 in. |
| P2490 | 7/8 in. | 15/16 in. |
Source: Unistrut® General Engineering Catalog no. 17, p. 90 — printed in the part table
What bolts through it, and where the published data stops.
Hardware. One 1/2 x 15/16 in. hex head cap screw and one 1/2 in. channel nut — P1010, P4010 or P5510 depending on the channel depth. Neither is supplied with the plate.
Where it goes. Flat on the open face of the channel, under the bolt head, with the channel nut turned into the lips beneath. It is the piece that turns a bolt through a bracket into a proper strut connection: the plate bears on both lips at once, so the clamp is not trying to dish a single lip under the washer.
Load rating. The catalog publishes no load figure for P1064, so neither do we. Where the catalog gives design load data for a fitting it states that it is based on the ultimate strength of the connection with a safety factor of 2.5; no such figure appears on p. 90 for this part.
What the published cross-reference tables print opposite P1064.
| Brand | Published cross-reference part number |
|---|---|
| B-Line | B202 [S1][S3] |
| Superstrut | AB-241-1/2 [S1][S3] |
| Power-Strut | PS 619 1/2 [S1][S3] |
| Haydon | F-201 1/2 [S3] |
A published cross-reference number is one thing only: a number a cited document prints opposite this one, as a candidate substitute in the same catalog slot. It carries no load rating, steel grade, coating thickness or third-party listing — each manufacturer publishes those separately and they do not travel with a part number. Source documents, access dates and what to measure before you fit a substitute: Unistrut P1064 cross reference.
Source: our cross-reference dataset, built 2026-09-09 from the documents listed below.
What a P1064 actually is
It is the plainest part in the catalog and the one most often left off the order. A square of steel plate exactly as wide as the channel, with one hole in it, sized so a half-inch bolt passes through with normal clearance. It does nothing except spread load and sit flat.
That matters more than it sounds. A bolt tightened directly onto the open face of a strut channel bears on two narrow lips, and a plain washer covers only part of each. The plate covers the whole face, so the clamping force goes into the lips evenly and the bracket above it cannot rock. It is also the piece that lets you bolt a flat item — a foot, a bracket, a piece of angle — to strut without buying a purpose-made fitting for it.
Choosing between the six plates
The six part numbers on that table are the same plate with six holes. Pick by the bolt you are going to use, not by what is in the bin: P1062 for a 5/16 in. bolt, P1063 for 3/8 in., P1064 for 1/2 in., P1964 for 5/8 in., P2471 for 3/4 in. and P2490 for 7/8 in. Using an oversized plate with a small bolt is not a saving; the bolt head has to cover the hole or you are back to needing a washer, and the hole edge is where a thin washer will deform.
The tapped group on the same catalog page — P1959, P1960 and P1961 — looks like the same part and is not. Those are threaded rather than drilled, and the catalog prints a separate material note for them at 3/8 in. thick. If a supplier offers a “1-5/8 square plate” without naming the part number, ask which of the two groups they mean and what thickness they are quoting.
Checking an incoming shipment
This part is so simple that the only failure modes are thickness and hole size, and both are quick.
1. Caliper the thickness and compare it with the thickness on your quotation. Anywhere on the plate, it is flat throughout. Thin stock is the quiet substitution on flat plate more than on any other fitting, because there is no bend or gusset to give the game away and the part photographs identically. Our standard plate is about 0.23 in. (5.8 mm) base steel before coating; a hot-dip galvanized part measures thicker. The catalog reference part is 1/4 in. (6.4 mm). Compare the base-steel thickness on your quotation; measure a galvanized part knowing the coating adds to it. A 3/16 in. (4.8 mm) plate looks the same in a bin — that is the one to reject.
2. Gauge the hole: 9/16 in. (14.3 mm). A 1/2 in. bolt must pass through without being driven. If a 1/2 in. bolt is tight, you have P1063 with a 7/16 in. hole in a P1064 box; if the bolt rattles, you probably have P1964 at 11/16 in.
3. Measure the square: 1-5/8 in. (41.3 mm) both ways. The plate has to be the width of the channel face. Oversize plate overhangs the run and fouls anything clamped alongside; undersize plate does not reach both lips, which defeats the purpose of using one.
Related parts
- P1065 — The two-hole version, 3-1/2 in. long — for tying two channels rather than clamping one item.
- P1026 — The bent two-hole 90° angle, when the two channels are at a right angle to each other.
- P1010 — The 1/2 in.-13 channel nut this plate bolts into.
- All flat plate fittings — The plate group on the fittings table.
- Finish options — PL, EG, HDG and stainless, and which of them we can supply.
What we can quote against this part number
We do not manufacture these parts and we are not Unistrut. We source them. The item we can quote against Unistrut P1064 is flat plate fitting, 1-5/8 in. square, one 9/16 in. hole — a candidate substitute made to order by a contract manufacturer, offered for inquiry, not an original-manufacturer part.
| Dimension | Value | Source |
|---|---|---|
| Plate size | 1-5/8 in. square (41.3 mm) | Unistrut® General Engineering Catalog no. 17, p. 90 — printed on the part drawing |
| Bolt size | 1/2 in. | Unistrut® General Engineering Catalog no. 17, p. 90 — printed in the part table |
| Hole size | 9/16 in. (14.3 mm) | Unistrut® General Engineering Catalog no. 17, p. 90 — printed in the part table |
| Holes | 1 | Unistrut® General Engineering Catalog no. 17, p. 90 — printed in the part table |
| Thickness | About 0.23 in. (5.8 mm) base steel before coating; a hot-dip galvanized part measures thicker. Steel grade confirmed at quotation. | Our supply specification — not a catalog figure |
These are the published Unistrut catalog dimensions we build to, each with the page it is printed on. The thickness row is the exception: it states what we supply, not a catalog figure. They are geometry only. No load, torque or listing figure is claimed for our part: none has been tested on it, and a figure published for a Unistrut part is evidence about that part, not about ours.
Supply summary
What is known about supplying this part number, and nothing that is not. Anything missing from this list is missing because we do not have it yet, not because it was left out.
- Reference part
- Unistrut® P1064, as published in the Unistrut® General Engineering Catalog no. 17
- What we quote against it
- flat plate fitting, 1-5/8 in. square, one 9/16 in. hole — a candidate substitute made to order by a contract manufacturer, offered for inquiry, not an original-manufacturer part.
- Plate thickness
- About 0.23 in. (5.8 mm) base steel before coating; a hot-dip galvanized part measures thicker. Steel grade confirmed at quotation.
- Finishes available
- Plain, EG, HDG and stainless, plus powder coating on request.
- Documents we can provide
- A dimension drawing traced from the catalog page cited above. A material certificate on request — availability and cost are confirmed at quotation, per mill.
- Lead time
- Production lead time: 5–7 business days, ex-factory. Counted from order confirmation and receipt of deposit (or drawing approval for custom parts, whichever is later). This does not include transit.
- How to confirm fit
- Measure the incoming parts against "Checking an incoming shipment" on this page, before the carton goes into stock.
Get this part number quoted
Answer the seven lines below and we come back with our part number, finish options, lead time, packing quantity and what documentation we can and cannot supply. There is no list price — it is quoted per mill, finish and volume. The form takes about a minute and already knows this part number. We reply within one business day (Asia/Shanghai, UTC+8).
- Unistrut part number — P1064
- The brand and part number you are replacing
- Finish
- Quantity
- Destination — country, and state or ZIP if US
- Application — general support, electrical, mechanical, seismic, or a listed assembly
- Whether you need submittal documentation
No minimum order · 5–7 business days ex-factory · Reply within one business day (Asia/Shanghai, UTC+8) · Finishes: plain, EG, HDG, stainless
Prefer email? Open a prefilled RFQ in your mail client, or write to contact@channelstrut.com yourself. If the part is going into a specification that names a brand, say so — a substitute has to be accepted in writing before it ships.
Trademarks and who we are
Unistrut, B-Line, Superstrut, Power-Strut and Haydon, and the part numbers published under them, are trademarks or trade names of their respective owners. ChannelStrut is not affiliated with, authorized by, endorsed by or a distributor for any of them. Those brand names and part numbers are used here only to identify the products referred to.
ChannelStrut is run by Alex, a hardware sourcing specialist based in Fujian, China. We do not manufacture these parts — we source them from the mills that produce them. More on how the data is built: About.
Sources
The cross-brand part numbers in the cross-reference tab come from S1 and S3. Every dimension on this page comes from the Unistrut® General Engineering Catalog no. 17, and the page it is printed on is given beside it.
- S1
- Divspec - Strut Fitting Cross Reference (Divspec / B-Line / Unistrut / Powerstrut / Superstrut(Thomas & Betts))
http://www.divspec.com/strut-fitting-cross-reference/
third-party aggregator · accessed 2026-09-09 - S3
- Master Distribution - Part Number Cross Reference Guide (G-Strut / Unistrut / Powerstrut / Superstrut / Erico / B-Line / PHD / Haydon), 23 pages
https://masterdistrib.com/content/PDF/Masterdistrib_Part_Number_Cross_Reference_Guide.pdf
third-party aggregator · accessed 2026-09-09
Every source above was re-checked for reachability on 2026-09-15.
Unistrut P1064 cross reference — what the published guides print opposite it, and what to measure on a substitute, or the full 126 part-number table.