# Toggle switch bushings and panel holes: 1/4-40, 15/32-32, M6 x 0.75, M12 x 1 (NKK, C&K 7000, Carling) + hole gauge

> What hole does a toggle switch need, and what are the 1/4-40, 15/32-32 and M12 bushing threads?

- Category: Electronic components › Panel cutouts
- Kind: Standard part
- Basis: NKK series P and M catalog pages, the C&K 7000 series datasheet and a Carling toggle listing, as read; one hole gauge plate as a file
- Page: https://xemstudio.com/objects/toggle-switch-bushings-panel-holes/ · JSON: https://xemstudio.com/api/geometry?object=toggle-switch-bushings-panel-holes · Plain text: https://xemstudio.com/objects/toggle-switch-bushings-panel-holes/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 |
|---|---|---|
| 55.5 | 24.7 | 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

- Miniature toggles use a 1/4-40 bushing (or M6 x 0.75 on the metric NKK versions), larger power toggles use 15/32-32 (Carling, C&K T / T1 actuators) or M12 x 1 (NKK 12 mm). The thread is the nominal major diameter: 6.35 mm for 1/4-40, about 11.9 mm for 15/32, 12 mm for M12 (the 15/32 figure is the inch size converted, not a printed number).
- Panel holes that are printed: NKK series P prints (6.35) / .250 in for the 6 mm bushing and (12.5) / .492 in for the 12 mm bushing; Carling's listing prints a circular 12.70 mm cutout for 15/32-32. The C&K 7000 datasheet read prints no hole number. NKK's catalog also draws (12.5) / .492 in for the large bushing, which agrees with series P. The 12.5 and 12.70 mm figures are different makers' holes for different bushings (M12 x 1 and 15/32-32), so they sit side by side on the gauge.
- Keyway and flat: NKK prints keyway and D-flat codes by bushing (listed above) and a keyway notch of (1.1) x (2.0) mm drawn with the 1/4-40 thread; this is the notch on the bushing, whose position in the panel is not printed as a labeled number, so no notch is drawn. C&K lists keyway bushings (D, D9, Y, Y9, H3, H4, Y1, Y3) and flat bushings (D8, H, Y4). Use the matching keyed washer; a keyway needs the hole cut with a notch or a tab washer.
- Panel thickness: NKK series P prints maximum thicknesses (.134 in / 3.4 mm, .102 in / 2.6 mm, .256 in / 6.5 mm, .217 in / 5.5 mm with keyway or locking ring) but the text read does not assign them to the 6 mm and 12 mm bushings, so they are not tabulated. C&K and Carling printed none.
- File: toggle-bushing-hole-gauge is a plate with the three published round holes at true size. Plate thickness 3 mm, spacing and corner radius are Xem's choices. Rockers: rocker-switch-panel-cutouts; wall-plate toggles: wall-plate-toggle-us; maker CAD is linked, not copied.

## 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 |
|---|---|---|---|---|
| panel hole 6.35 mm (file toggle-bushing-hole-gauge) | round hole 6.35 mm = .250 in (NKK series P) | 1/4-40 or M6 x 0.75 toggle bushing; the bushing passes through, a nut or locking ring clamps it | slide | toggle-bushing-hole-gauge* |
| panel hole 12.5 mm (file toggle-bushing-hole-gauge) | round hole 12.5 mm = .492 in (NKK series P and M large bushing) | NKK 12 mm M12 x 1 toggle bushing | slide | toggle-bushing-hole-gauge* |
| panel hole 12.70 mm (file toggle-bushing-hole-gauge) | round hole 12.70 mm (Carling 110-73 circular cutout) | 15/32-32 toggle bushing | slide | toggle-bushing-hole-gauge* |

## Sizes

| maker / series | bushing / actuator | thread | panel hole (as printed) | keyway / flat | source |
|---|---|---|---|---|---|
| NKK series P | 6 mm bushing (.512 in white cap / .450 in flatted toggle) | thread M6 P0.75 | panel hole (6.35) = .250 in | keyway (flatted toggle E) | NKK series P catalog pages |
| NKK series P | 12 mm bushing (.689 in large bat / .748 in white capped column) | thread M12 P1 | panel hole (12.5) = .492 in | keyway | NKK series P catalog pages |
| NKK series M | S1, A1, D1, L1 small bushings | 1/4-40; S1 bushing length .350 in (8.9 mm), A1 .280 in (7.1 mm) | not labeled for the small bushings on these pages (a drawn .315 in / 8.0 mm is unlabeled and not used) | keyway on S1, S2, A1, A2, S4, B1, L1, L2, L4; D-flat on D1, D3, D4, D8, L3, L8, B3; keyway notch (1.1) x (2.0) mm = .043 x .079 in drawn with the 1/4-40 thread | NKK series M catalog pages |
| NKK series M | S4, D4, D8, L4, L8 6 mm bushings | M6 P0.75 | see series P | see keyway / D-flat list above | NKK series M catalog pages |
| NKK series M | B1, B3 large bushings | 12 mm (.472 in) thread, M12 P1 | (12.5) dia .492 in in the panel cutout drawing | B1 keyway; B3 D-flat | NKK series M catalog pages |
| C&K 7000 | T and T1 actuators | 15/32-32 UNS-2A | not printed | bushing codes D, Y, H3, H4, Y1, Y3, Y9, D9 are keyway; D8, H, Y4 are flat | C&K 7000 datasheet |
| C&K 7000 | all other actuators | 1/4-40 UNS-2A | not printed | same bushing codes | C&K 7000 datasheet |
| C&K 7000 | bushing heights | D, D8, D9 .280 in; Y, Y9 .350 in; H .296 in; H3 .315 in; Y1, Y4 .378 in; H4 8 mm (metric, high torque, keyway); Y3 8.9 mm (metric, keyway) | not printed | add .070 in (1.78 mm) to actuator lengths for D, D8, D9; hardware: two mounting nuts, one locking ring, one lockwasher with threaded bushings | C&K 7000 datasheet |
| Carling toggle 110-73 | standard toggle | 15/32-32 | circular 12.70 mm | not stated | Carling 110-73 listing |

## Where the files are

- NKK Switches: [Series P toggle switches (P2011 to P2023): bushing M6 P0.75 and M12 P1, panel hole (6.35) and (12.5), keyway, hardware part numbers](https://deramp.com/downloads/mfe_archive/050-Component%20Specifications/Switches/NKK%20PToggles.pdf) — web — Maker catalog pages (archive copy); numbers only
- NKK Switches: [Series M miniature toggle catalog pages A52-A63 (M2012 / M2021 family): bushings S1, A1, D1, L1 (1/4-40), S4 / D4 / D8 / L4 / L8 (M6 x 0.75), B1 / B3 (M12 x 1), keyway and D-flat](https://www.nyang-tech.com/datasheet/41330281449/NKK-Switches/M2021LL3G01.pdf) — web — Maker catalog pages (distributor copy); numbers only
- C&K (Littelfuse): [7000 series miniature toggle datasheet: bushing codes (D, D8, D9, Y, Y1, Y3, Y4, H, H3, H4, CW), 1/4-40 UNS-2A and 15/32-32 UNS-2A threads, keyway and flat](https://www.digikey.de/en/htmldatasheets/production/1205415/0/0/2/7103syzqe) — web — Maker datasheet (DigiKey HTML copy); numbers only
- Carling Technologies: [Toggle switch 110-73 (GlobalSpec datasheet listing): panel cutout circular 12.70 mm, bushing thread 15/32-32](https://datasheets.globalspec.com/ds/carling-technologies/110-73/13f5092e-0ed2-4f80-88c9-bef9a2ed2187) — web — Maker listing; numbers only
- NKK Switches: [NKK Switches product pages (M-series and S-series toggles) with 3D CAD downloads per part](https://www.nkkswitches.com/) — web — Maker site; CAD per part from the maker
- C&K (Littelfuse): [C&K 7000 series toggle product page (3D models per part)](https://www.ckswitches.com/products/switches/product-details/Toggle/7000?page=6) — web — Maker page; CAD per part from the maker

## Free STEP/STL (1 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/toggle-switch-bushings-panel-holes/index.json

- toggle-bushing-hole-gauge-6p35-12p5-12p7: [STEP](https://xemstudio.com/files/hardware/toggle-switch-bushings-panel-holes/toggle-bushing-hole-gauge-6p35-12p5-12p7.step) · [STL](https://xemstudio.com/files/hardware/toggle-switch-bushings-panel-holes/toggle-bushing-hole-gauge-6p35-12p5-12p7.stl) — hole gauge plate, 55.5 x 24.7 x 3 mm, three round holes at the published panel holes 6.35 mm (.250 in, NKK 1/4-40 and M6 bushings), 12.5 mm (.492 in, NKK 12 mm M12 x 1 bushing) and 12.70 mm (Carling 15/32-32 bushing), smallest first, 6 mm between hole edges and 6 mm of plate round the largest hole; no keyway notch is drawn (its position is not printed as a labeled number); plate thickness and spacing are Xem choices

## Questions

**What hole does a mini toggle switch need?**

NKK series P prints a 6.35 mm (.250 in) panel hole for its 6 mm (M6 x 0.75) bushing; 1/4-40 bushings are the same 1/4 in size. The C&K 7000 sheet read prints no hole number.

**What hole for a 15/32-32 toggle?**

Carling's listing prints a circular 12.70 mm cutout for 15/32-32. NKK's 12 mm M12 x 1 bushing is (12.5) mm / .492 in.

**Do toggle switches have a keyway?**

Yes on many bushings: NKK S1, S2, A1, A2, S4, B1, L1, L2, L4 are keyway and D1, D3, D4, D8, L3, L8, B3 are D-flat; C&K D, D9, Y, Y9, H3, H4, Y1, Y3 are keyway.

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