# PEM self-clinching nuts (S, CLS, CLSS): hole size, minimum edge distance, nut diameter and height, M2–M12 and #2-56 to 3/8-24 + hole gauges

> What hole size and edge distance for a PEM self-clinching nut, and what is the clinch nut hole for M3, M4 or M6?

- Category: Hardware › Fasteners
- Kind: Standard part
- Basis: PennEngineering (PEM) product-finder and catalog pages for the Unified and Metric S, CLS, CLSS series, read part by part; two hole gauges as files
- Page: https://xemstudio.com/objects/pem-self-clinching-nuts-s-cls/ · JSON: https://xemstudio.com/api/geometry?object=pem-self-clinching-nuts-s-cls · Plain text: https://xemstudio.com/objects/pem-self-clinching-nuts-s-cls/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

## Overall (mm)

| length | width | height |
|---|---|---|
| 98.2 | 25.0 | 3.0 |

**Exact dimensions.** Every file is drawn at true size with no tolerance added. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your process's clearance before making the part.

## Notes

- Rows are the values PEM prints on one representative part page per thread (named in the page column); hole size in sheet is +0.08 mm / +.003 −.000 in; E and T carry ±0.25 mm / ±.010 in; C max is the maximum of the clinch body (it is 0.02 mm / .001 in under the hole size on every row); the minimum distance from the hole centreline to the sheet edge is a minimum. The page for CLS-256-2 states: use a centreline-to-edge value 'greater or equal to the value specified', and recommends the maximum shank length for your sheet thickness. For use in sheet hardness: HRB 70 / HB 125 or less for CLS / CLSS (the S-type pages listed the same in the compare table). Thread specs: metric 6H ASME B1.13M, unified 2B ASME B1.1.
- Minimum sheet thickness: PEM prints a 'rec. min. sheet thickness' only on the CLS-256-2 page (.056 in, for shank code 2); none of the other part pages read give one, so it is not tabulated. It depends on the shank code (A max: M2 / M2.5 / M3 codes 0, 1, 2 are .77 / .97 / 1.38 mm; #2-56 and #4-40 codes 0, 1, 2, 3 are .030 / .038 / .054 / .087 in; as printed on the catalog lists). Use PEM's data sheet for minimum thickness by shank code.
- Gaps, stated plainly: the #3-48 row carries only the hole and E from the catalog list (hole .166, E .250); M12 only the catalog list's hole 17 and E 20.57 for S-M12-1ZI. The M3, M4, M6 and M8 shank code printed varies by the part read (CLS-M3-1, CLS-M4-2, CLS-M6-1, CLS-M8-1) and A is shown for that code only. M5 is from the CLSS (SS-series) page; CLS / S M5 was not read.
- Files are two hole gauges (plates with the published nominal hole sizes, smallest first; 3 mm plate, 4 mm gap and 4 mm margin chosen by Xem). The nut itself is PEM's part: its CAD is on PEM's product pages and is not rehosted. PEM's thread masking and torque pages were not read. Weld nuts: weld-nuts-din-929; rivet nuts: rivet-nuts-flat-head.

## Mating features (exact size; open press / slide / run / socket by your process clearance, leave designed and clamp as drawn)

| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| hole in sheet (nut) | M2 / M2.5 / M3 Ø4.22, M4 5.41, M5 6.35, M6 8.75, M8 10.5, M10 14, M12 17 mm (+0.08); #2-56 to #4-40 .166, #6-32 .1875, #8-32 .213, #10-32 .250, 3/8-24 .500 in (+.003 / −.000) | PEM S / CLS / CLSS self-clinching nut pressed into the sheet | press | clinch-hole-gauge-* |
| edge distance | min hole centre to sheet edge: M2 to M3 4.8, M4 6.9, M5 7.1, M6 8.6, M8 9.7, M10 13.5 mm; #2-56 .190, #6-32 .220, #8-32 .270, #10-32 .280, 3/8-24 .440 in | sheet edge keep-out | designed | clinch-hole-gauge-* |

## Sizes

| system | thread | hole in sheet | E | T | C max | min. dist. hole C/L to edge | part page read | A shank max by code (as printed) |
|---|---|---|---|---|---|---|---|---|
| metric (mm) | M2 x 0.4 | 4.22 | 6.35 | 1.5 | 4.2 | 4.8 | CLS-M2-2 | 0 .77, 1 .97, 2 1.38 |
| metric (mm) | M2.5 x 0.45 | 4.22 | 6.35 | 1.5 | 4.2 | 4.8 | CLS-M2.5-1 | 0 .77, 1 .97, 2 1.38 |
| metric (mm) | M3 x 0.5 | 4.22 | 6.35 | 1.5 | 4.2 | 4.8 | CLS-M3-1 | 1 .97 (page) |
| metric (mm) | M4 x 0.7 | 5.41 | 7.87 | 2 | 5.38 | 6.9 | CLS-M4-2 | 2 1.38 (page) |
| metric (mm) | M5 x 0.8 | 6.35 | 8.64 | 2 | 6.33 | 7.1 | CLSS-M5-1 | (not printed) |
| metric (mm) | M6 x 1 | 8.75 | 11.18 | 4.08 | 8.73 | 8.6 | CLS-M6-1 | 1 1.38 (page) |
| metric (mm) | M8 x 1.25 | 10.5 | 12.7 | 5.47 | 10.47 | 9.7 | CLS-M8-1 / -2 | 1 1.38, 2 2.21 |
| metric (mm) | M10 x 1.5 | 14 | 17.35 | 7.48 | 13.97 | 13.5 | CLS-M10-2 | 1 2.21, 2 3.05 |
| metric (mm) | M12 x 1.75 | 17 | 20.57 | — | — | — | S-M12-1ZI (catalog list) | 1 3.05 |
| unified (in) | #2-56 (.086) | .166 | .250 | .070 | .165 | .190 | CLS-256-2 | 0 .030, 1 .038, 2 .054 |
| unified (in) | #3-48 (.099) | .166 | .250 | — | — | — | list (CLS-348-n) | 0 .030, 1 .038, 2 .054 |
| unified (in) | #4-40 (.112) | .166 | .250 | .070 | .165 | .190 | CLS-440-3 | 0 .030, 1 .038, 2 .054, 3 .087 |
| unified (in) | #6-32 (.138) | .1875 | .280 | .070 | .187 | .220 | CLS-632-0 | 0 .030 |
| unified (in) | #8-32 (.164) | .213 | .310 | .090 | .212 | .270 | CLS-832-2 | 2 .054 |
| unified (in) | #10-32 (.190) | .250 | .340 | .090 | .249 | .280 | CLSS-032-3 / -2 | 3 .087 |
| unified (in) | 3/8-24 (.375) | .500 | .560 | .270 | .499 | .440 | CLS-0624-1 | 1 .087 (page) |

## Where the files are

- PennEngineering (PEM): [Self-clinching nuts types S, SS, CLS, CLSS, SP: product-finder pages CLS-M2-2, CLS-M2.5-1, CLS-M3-1, CLS-M4-2, CLS-M6-1, CLS-M8-1, CLS-M10-2, CLSS-M5-1, CLS-256-2, CLS-440-3, CLS-632-0, CLS-832-2, CLSS-032-3, CLS-0624-1](https://catalog.pemnet.com/viewitems/nuts-types-s-ss-cls-clss-cla-sp/self-clinching-nuts-types-s-ss-cls-clss-sp-unified?plpver=10) — web — Manufacturer catalog; dimensions are facts; CAD is PEM's, not hosted
- McMaster-Carr: [Press-fit (self-clinching) nuts (free STEP/IGES per part, for your own design use; no redistribution)](https://www.mcmaster.com/products/press-fit-nuts/thread-size~m6-2/) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution (verify at link)

## Free STEP/STL (2 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/pem-self-clinching-nuts-s-cls/index.json

- clinch-hole-gauge-pem-nuts-metric-m2-m12: [STEP](https://xemstudio.com/files/hardware/pem-self-clinching-nuts-s-cls/clinch-hole-gauge-pem-nuts-metric-m2-m12.step) · [STL](https://xemstudio.com/files/hardware/pem-self-clinching-nuts-s-cls/clinch-hole-gauge-pem-nuts-metric-m2-m12.stl) — hole gauge plate, 98.2 × 25.0 × 3 mm, seven holes at PEM's hole size in sheet for S / CLS / CLSS nuts: Ø4.22 (M2, M2.5, M3), 5.41 (M4), 6.35 (M5), 8.75 (M6), 10.5 (M8), 14 (M10), 17 (M12) mm, nominal = lower limit of the +0.08 mm tolerance; plate thickness and spacing are Xem choices
- clinch-hole-gauge-pem-nuts-inch-2-56-to-3-8: [STEP](https://xemstudio.com/files/hardware/pem-self-clinching-nuts-s-cls/clinch-hole-gauge-pem-nuts-inch-2-56-to-3-8.step) · [STL](https://xemstudio.com/files/hardware/pem-self-clinching-nuts-s-cls/clinch-hole-gauge-pem-nuts-inch-2-56-to-3-8.stl) — hole gauge plate, 57.4 × 20.7 × 3 mm, five holes at PEM's hole size in sheet for S / CLS / CLSS nuts: .166 (#2-56 to #4-40), .1875 (#6-32), .213 (#8-32), .250 (#10-32), .500 (3/8-24) in, nominal = lower limit of the +.003 / −.000 in tolerance; plate thickness and spacing are Xem choices

## Questions

**What hole size does an M3 PEM self-clinching nut need?**

4.22 mm (+0.08), with the hole centre at least 4.8 mm from the sheet edge (CLS-M3-1; M2 and M2.5 are the same).

**What hole for an M6 PEM CLS nut?**

8.75 mm (+0.08), edge distance 8.6 mm min, E 11.18 mm, T 4.08 mm (CLS-M6-1).

**What is the minimum sheet thickness for a PEM nut?**

PEM prints it by shank code; the only value read is .056 in for CLS-256-2. Check PEM's data sheet for others.

## Fits with

- [PEM self-clinching standoffs (SO, SOS, SOA and blind BSO): hole size, sheet thickness, edge distance, M3–M5 and #4-40 to #10-32 + hole gauges](https://xemstudio.com/objects/pem-self-clinching-standoffs-so-bso/)
- [PEM self-clinching studs (FH, FHS, FHLS): hole size, minimum sheet thickness, edge distance, #2-56 to #8-32 and M3–M4 + hole gauges](https://xemstudio.com/objects/pem-self-clinching-studs-fh/)
- [Rivet nuts (blind threaded inserts), flat head: hole size, grip range, body and flange dimensions, M3–M12 and #6-32 to 3/8-16](https://xemstudio.com/objects/rivet-nuts-flat-head/)
- [Hex weld nuts, DIN 929: M3–M16 pilot diameter, height, across flats, sheet thickness range](https://xemstudio.com/objects/weld-nuts-din-929/)
- [Hex nuts, M2–M8 (ISO 4032)](https://xemstudio.com/objects/hex-nuts-metric/)
- [Threaded standoffs, M2.5 and M3 (hex and round)](https://xemstudio.com/objects/threaded-standoffs-metric/)
- [Heat-set threaded inserts, metric: M2 to M10, standard, short and Voron (CNC Kitchen sizes)](https://xemstudio.com/objects/heat-set-inserts/)