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Automotive blade fuses (ISO 8820-3 / SAE J1284): Micro2, Micro3, low-profile mini, mini ATM, regular ATO/ATC, maxi: body width, thickness, height
What are the dimensions of Micro2, Micro3, mini (ATM), low-profile mini, regular (ATO / ATC) and maxi automotive blade fuses, and what is the blade spacing? · Standard part · basis: Wikipedia/YourSpec blade fuse table cross-checked with Wiltronics labelled pages and a Bussmann ATM listing; blade spacing only where a labelled value was readable; McMaster-Carr linked for CAD
Also called: blade fuse dimensions, ato fuse size, atc fuse dimensions, atm mini fuse dimensions, micro2 fuse dimensions, micro3 fuse size, low profile mini fuse size, maxi fuse dimensions, car fuse size chart, automotive fuse sizes, blade fuse blade spacing, standard blade fuse 19.1 mm, mini blade fuse 10.9 mm, iso 8820-3, sae j1284, apt atr fuse, apm atm fuse, apx maxi fuse size, fuse box slot size
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. Mating features
- sizes
- 6 in table
Notes
- Blade (tab) fuses are named by body size: Micro2, Micro3, low-profile mini, mini (ATM), regular (ATO / ATC) and maxi. The road-vehicle fuse-link standard is ISO 8820, whose part 3 covers fuse-links with tabs (blade type); the ATO / ATC regular size is the SAE J1284 form. Littelfuse's MICRO2 page cites 'SAE 2741-1 and ISO 8820-12:2020' for that size, so the part numbers differ between sizes. Check the part you hold against the standard edition your holder was made to.
- Body width, thickness and height: the Wikipedia (and YourSpec) table prints each as L x W x H; the three sizes Wiltronics lists agree and label them width, depth and height (regular 19.1 / 5.1 / 18.5, maxi 29.2 / 8.5 / 34.3, mini 10.9 / 3.6 / 16.3). Micro2, Micro3 and LP-mini come from the Wikipedia / YourSpec table only.
- Where sources disagree: the ATM mini thickness. Wikipedia and Wiltronics print 3.6 mm; a Bussmann ATM 15 listing gives 0.150 in (3.81 mm) with 0.430 in (10.92 mm) width and 0.642 in (16.31 mm) height, and the Eaton data sheet's readable numbers (.430, .15) agree with the listing. Both are shown; the 3.6 may be a rounded or per-maker value. The LP-mini thickness 3.81 is the Wikipedia figure (the Littelfuse LP-mini sheet's drawing numbers 3.8, 10.9 and 8.4 are unlabelled in the copy read).
- Blade spacing is the centre-to-centre distance of the two blades, which sets the holder slot. Only two values could be read with a label: Micro2 5.0 mm (Prolec catalogue text: 'a smaller 5.0 mm centerline spacing') and ATC / ATO 5.08 mm (0.2 in). Blade width and thickness for all six sizes are printed in outline drawings that the reader could not turn into labelled numbers, so they are left out rather than guessed.
- No files: a fuse with blades is not fully defined by the body numbers, and a plain body block is not a useful model. Left out: current ratings and colour codes, voltage ratings (32 V and 58 V versions), blade length and width, the sub-miniature three-blade types and ATO-F flange versions.
- McMaster-Carr stocks ATO, ATM and maxi fuses and holders with free per-part STEP/IGES; the category links are below (linked only, not hosted here).
Automotive blade fuses (ISO 8820-3 / SAE J1284): Micro2, Micro3… size chart
| fuse size | blade group codes (maker names) | body width, mm | body thickness (depth), mm | height, mm (body + blades, as listed) | blade spacing, mm |
|---|---|---|---|---|---|
| Micro2 | APT, ATR | 9.1 | 3.8 | 15.3 | 5.0 (Prolec catalogue text) |
| Micro3 | ATL | 14.4 | 4.2 | 18.1 | not read |
| Low-profile mini (LP-mini) | APS, ATT | 10.9 | 3.81 | 8.73 | not read |
| Mini (ATM) | APM, ATM | 10.9 | 3.6 | 16.3 | not read |
| Regular / standard (ATO, ATC) | APR, ATC, ATO, ATS | 19.1 | 5.1 | 18.5 | 5.08 (0.2 in; SpecFits) |
| Maxi | APX | 29.2 | 8.5 | 34.3 | not read |
Mating features
Drawn at the exact size. Open press, slide, run and socket features by your process's clearance (tolerances by process); leave designed gaps and clamp fits as drawn.
| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| regular ATO / ATC blade fuse | body 19.1 wide × 5.1 thick × 18.5 tall; blade spacing 5.08 | fuse holder slot for the regular size (holder maker's drawing governs) | designed | all |
| mini ATM blade fuse | body 10.9 wide × 3.6 (or 3.81) thick × 16.3 tall | mini fuse holder slot (holder maker's drawing governs) | designed | all |
| maxi blade fuse | body 29.2 wide × 8.5 thick × 34.3 tall | maxi fuse holder slot (holder maker's drawing governs) | designed | all |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
Xem scan
File coming
No downloadable true-size file yet: the published figures do not fix the whole shape, and Xem never guesses a number. A measured scan is planned; request it and it moves 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=automotive-blade-fuses-iso-8820-3
Fits with
Questions
How big is a regular ATO / ATC blade fuse?
19.1 mm wide, 5.1 mm thick and 18.5 mm tall, with blades 5.08 mm (0.2 in) apart (SpecFits).
How big is a mini (ATM) blade fuse?
10.9 mm wide, 16.3 mm tall and 3.6 mm thick (Wikipedia, Wiltronics) or 3.81 mm (0.150 in, Bussmann listing); the page shows both.
How big is a Micro2 fuse?
9.1 mm wide, 3.8 mm thick, 15.3 mm tall; blade spacing 5.0 mm.
How big is a maxi blade fuse?
29.2 mm wide, 8.5 mm thick and 34.3 mm tall.