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A21 light bulb (E26 base)
What size is an A21 light bulb? · Modern device · basis: Philips product datasheet (Philips 16A21/PER/830/P/E26/DIM)
Also called: a21 bulb size, a21 dimensions, a21 light bulb dimensions, bombilla A21 medidas, lâmpada A21 dimensões, A21 Lampe Maße, ampoule A21 dimensions
Exact dimensions. True size, with no printing tolerance added.
- length
- 78 mm
- width
- 78 mm
- height
- 140 mm
Notes
- A21: Ø78 mm, 140 mm maximum overall length, E26 base — figures from the Philips 16A21/PER/830/P/E26/DIM datasheet.
- The shape code gives the diameter in eighths of an inch (A21); the ANSI C78 envelope limits are paywalled, so a typical current product is quoted. Other brands differ by a few mm in length.
- The file is a cylinder envelope Ø × MOL (the bulb fits inside it).
A21 light bulb size chart
| dimension | value |
|---|---|
| diameter | 78 mm (3.07 in) |
| max overall length | 140 mm (5.51 in) |
| base | E26 |
| reference product | Philips 16A21/PER/830/P/E26/DIM |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
| Philips | Philips 16A21/PER/830/P/E26/DIM datasheet | web | Publisher's page; dimensions are facts |
Free files
★ Free files 1 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json
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Set it up →https://xemstudio.com/mcp to Claude, ChatGPT, Cursor or any MCP client (free, no account, one minute) and it can look up exact sizes, mating fits and free STEP/STL from every chat.Plain text: sheet.txt · JSON: /api/geometry?object=a21-light-bulb

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Questions
How big is an A21 bulb?
About Ø78 × 140 mm (reference product).