# Adafruit SGP40 air quality sensor (#4829, STEMMA QT): 25.4 × 17.78 mm board and 4 mounting holes

> What are the Adafruit SGP40 (product 4829) breakout dimensions and mounting-hole positions?

- Category: Electronic components › Modules, sensors & displays
- Kind: Modern device
- Basis: Adafruit's EagleCAD board file for the SGP40 STEMMA QT breakout, with connector height from the JST SH datasheet.
- Page: https://xemstudio.com/objects/adafruit-sgp40-4829/ · JSON: https://xemstudio.com/api/geometry?object=adafruit-sgp40-4829 · Plain text: https://xemstudio.com/objects/adafruit-sgp40-4829/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 |
|---|---|---|
| 25.4 | 17.78 | 4.55 |

**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

- Board 25.40 × 17.78 with R2.54 corners, centred, board bottom at 0. Board thickness 1.6 is assumed (Adafruit's board file does not state it); everything else is from the board file.
- Four plated Ø2.5 mounting holes at (±10.16, ±6.35) from the board centre: a 20.32 × 12.70 rectangle.
- Two STEMMA QT (JST SH 4-pin) connectors on the short edges, openings facing outward; 4.55 overall height.
- Not modelled: the loose 1×5 0.1 in header along one long edge and the 2.44 × 2.44 SGP40 sensor; leave the sensor open to air.
- All dimensions are exact nominal millimetres, true size, with no tolerance added.

## 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 |
|---|---|---|---|---|
| Mounting holes | 4 × Ø2.5 on 20.32 × 12.70 | M2.5 or #2-56 screws and standoffs | designed | all |
| STEMMA QT connectors | 2 × JST SH 4-pin, 4.25 × 6.10, top 4.55, openings on both short edges | JST SH 4-pin cable plug; leave cable clearance past each short edge | designed | all |

## Sizes

| hole | x (mm) | y (mm) | diameter (mm) |
|---|---|---|---|
| 1 | -10.16 | -6.35 | 2.5 |
| 2 | +10.16 | -6.35 | 2.5 |
| 3 | -10.16 | +6.35 | 2.5 |
| 4 | +10.16 | +6.35 | 2.5 |

## Where the files are

- Adafruit: [Adafruit SGP40 Air Quality Sensor Breakout - STEMMA QT (#4829)](https://www.adafruit.com/product/4829) — web — Publisher's page; dimensions are facts
- Adafruit: [Adafruit-SGP40-PCB repository](https://github.com/adafruit/Adafruit-SGP40-PCB) — web — Publisher's page; dimensions are facts
- Adafruit Learning System: [Adafruit SGP40 Air Quality Sensor guide](https://learn.adafruit.com/adafruit-sgp40) — web — Publisher's page; dimensions are facts
- JST: [SH connector series datasheet](https://www.jst-mfg.com/product/pdf/eng/eSH.pdf) — web — Publisher's page; dimensions are facts

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

Index: https://xemstudio.com/files/hardware/adafruit-sgp40-4829/index.json

- adafruit-sgp40-4829: [STEP](https://xemstudio.com/files/hardware/adafruit-sgp40-4829/adafruit-sgp40-4829.step) · [STL](https://xemstudio.com/files/hardware/adafruit-sgp40-4829/adafruit-sgp40-4829.stl) — Adafruit SGP40 air quality sensor (#4829, STEMMA QT): 25.4 × 17.78 mm board and 4 mounting holes

## Questions

**How big is the Adafruit SGP40 breakout?**

25.40 × 17.78 mm, 1.6 mm board (assumed), 4.55 mm tall over the STEMMA QT connectors.

**Where are its mounting holes?**

Four Ø2.5 holes on a 20.32 × 12.70 mm rectangle centred on the board.

## Fits with

- [Adafruit STEMMA QT sensor breakouts (BME280, BNO055/085, VL53, SCD-40, AHT20, SHT40, IMUs, light, magnet, RTC…)](https://xemstudio.com/objects/adafruit-stemma-qt-breakouts/)
- [JST SH connector (1.0 mm pitch): wire, ratings, circuits](https://xemstudio.com/objects/jst-sh-connector/)
- [Threaded standoffs, M2.5 and M3 (hex and round)](https://xemstudio.com/objects/threaded-standoffs-metric/)
- [2.54 mm pin headers, 1×2 to 2×20, vertical and right-angle](https://xemstudio.com/objects/pin-headers-2.54mm/)
- [Adafruit VL53L0X ToF distance sensor (#3317, STEMMA QT): 25.4 × 17.78 mm board, 4 mounting holes and sensor window](https://xemstudio.com/objects/adafruit-vl53l0x-3317/)
- [Adafruit BME280 breakout (original)](https://xemstudio.com/objects/adafruit-bme280-breakout-original/)