# Griping about part numbers and serial numbers **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [April 5, 2023, 2:53pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208 "2023-04-05T14:53:21Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [April 5, 2023, 2:53pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/1 "2023-04-05T14:53:21Z")
O.K. manufacturers, look, you should _never_ use the letter S in a model number, part number, serial number, inventory number, _whatever_. I just ran in to this today. It looks like a damn 5. And when I write it down, I use $ instead of S, just to remind myself that it’s an S and not a 5. Likewise, try your best to not use a 5, because it (duh) looks like an S. (Though this is not a big deal if there’s nothing but numbers.) S, of course, is the worst. But almost as bad is a lowercase L (l), upper case I, or the number 1. Please, just don’t do it. The letter O and zero (0) are bad, too. If you insist on using zero, put a damn slash through it or something. Better yet, just don’t use them. ---
**Author:** ![What\_Exit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/what_exit/32/10652_2.png) [@What\_Exit](https://boards.straightdope.com/u/What_Exit)\ **Post date:** [April 5, 2023, 2:55pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/2 "2023-04-05T14:55:39Z")
You’re not wrong, but for the last 12 years, I’ve usually just taken a picture of the label with the Model and Serial Number on it so this is no longer a problem for me. I got into the habit for many reasons including S and 5 confusion. Though mainly just accuracy. Phones and their cameras are an awesome tool. ---
**Author:** ![Procrustus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/procrustus/32/2994_2.png) [@Procrustus](https://boards.straightdope.com/u/Procrustus)\ **Post date:** [April 5, 2023, 3:01pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/3 "2023-04-05T15:01:19Z")
> [@What\_Exit](#): > > You’re not wrong, but for the last 12 years, I’ve usually just taken a picture of the label with the Model and Serial Number on it so this is no longer a problem for me. I got into the habit for many reasons including S and 5 confusion. Though mainly just accuracy. True for S and 5, not for O ad 0. No amount of magnification can fix that. ---
**Author:** ![Pleonast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pleonast/32/1183_2.png) [@Pleonast](https://boards.straightdope.com/u/Pleonast)\ **Post date:** [April 5, 2023, 3:06pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/4 "2023-04-05T15:06:32Z")
Letters and numbers shouldn’t be mixed. Okay, I’ll allow hexadecimal numbers, but no more. ---
**Author:** ![What\_Exit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/what_exit/32/10652_2.png) [@What\_Exit](https://boards.straightdope.com/u/What_Exit)\ **Post date:** [April 5, 2023, 3:07pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/5 "2023-04-05T15:07:11Z")
I disagree, I grabbed the first example in hardware folder. [![](https://i.postimg.cc/wvnggZMV/775-PC-73149-19-2v-Chainsaw-motor.jpg) ](https://i.postimg.cc/wvnggZMV/775-PC-73149-19-2v-Chainsaw-motor.jpg) I can see a clear difference between the O in motor and 0 in 121015. once I zoom in. Many computer related parts use the zero with the diagonal slash through it which is a huge help. Here is a more standard tag: [![](https://i.postimg.cc/Ghdht0z7/Drill-Press-20220116.jpg) ](https://i.postimg.cc/Ghdht0z7/Drill-Press-20220116.jpg) ---
**Author:** ![Procrustus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/procrustus/32/2994_2.png) [@Procrustus](https://boards.straightdope.com/u/Procrustus)\ **Post date:** [April 5, 2023, 3:09pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/6 "2023-04-05T15:09:53Z")
> [@What\_Exit](#): > > I can see a clear difference between the O in motor and 0 in 121015. once I zoom in I can’t. And sometimes there aren’t two to compare. Just one in the mix of letters and numbers. ---
**Author:** ![Pleonast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pleonast/32/1183_2.png) [@Pleonast](https://boards.straightdope.com/u/Pleonast)\ **Post date:** [April 5, 2023, 3:11pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/7 "2023-04-05T15:11:10Z")
> [@What\_Exit](#): > > I can see a clear difference between the O in motor and 0 in 121015. Really? Are you comparing the first or second O in motor? The differences seem more like random variances in the printing process. ---
**Author:** ![What\_Exit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/what_exit/32/10652_2.png) [@What\_Exit](https://boards.straightdope.com/u/What_Exit)\ **Post date:** [April 5, 2023, 3:14pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/8 "2023-04-05T15:14:34Z")
Sorry, I lost Internet connection during my post. I’m having some electrical work done as part of a kitchen refurb. I think the second example I posted is one where it is easy to see a difference. I’ll admit the first was tough. But the O’s are more rounded. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [April 5, 2023, 4:31pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/9 "2023-04-05T16:31:32Z")
There are fonts where O & 0 look very different. There are fonts where O & 0 look very similar. Especially when dot-matrixed years ago onto a now-dirty part. Guess which fonts are more common on things like this? The latter of course. I have my secure password generator configured to avoid using any of the look-alike letters/numbers. Avoids a lot of squinting and guesswork at little loss of entropy. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [April 5, 2023, 4:31pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/10 "2023-04-05T16:31:37Z")
Well, it depends on the font. There are fonts where the ‘O’ and the ‘0’ are identical. e.g. - Arizona license plates. But, most of these issues could be avoided by not using a sanserif font - but I guess that’s too unhip. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [April 5, 2023, 4:32pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/11 "2023-04-05T16:32:28Z")
Where exactly do you attach a serif to a O or a 0? I can see serifs maybe helping for l vs 1 and 5 vs S. ---
**Author:** ![abcdefghij](https://avatars.discourse-cdn.com/v4/letter/a/43a26b/32.png) [@abcdefghij](https://boards.straightdope.com/u/abcdefghij)\ **Post date:** [April 5, 2023, 4:40pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/12 "2023-04-05T16:40:40Z")
> [@LSLGuy](#): > > Where exactly do you attach a serif to a O or a 0? Like this: Q ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [April 5, 2023, 4:44pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/13 "2023-04-05T16:44:56Z")
Another way to avoid this whole issue is to provide the serial number in barcode or QR code format, so the user could just scan it. (One of the worst examples I’ve found is the serial number on the back of an Apple iPhone, printed in what appears to be 2point. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [April 5, 2023, 4:45pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/14 "2023-04-05T16:45:09Z")
It’s true that serifs don’t help the O vs 0 issue, but most serif fonts have those two characters drawn significantly differently anyway. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [April 5, 2023, 5:00pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/15 "2023-04-05T17:00:21Z")
> [@abcdefghij](#): > > > [@LSLGuy](#): > > > > Where exactly do you attach a serif to a O or a 0? > > Like this: Q So says the person whose name is @abcdefghij. A true letterophile if ever I’ve seen one. Next thing you’ll be wanting an l or an I on your name. I know your type; just insatiable for more letters. 🙂 ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [April 5, 2023, 7:27pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/16 "2023-04-05T19:27:35Z")
In keeping a database that only I use, I enter 0 and O as 0. I letter instead of write, so one can tell the difference, the top of the 5 is flat, I put a slash through zeroes. As many of you said, the font is at fault. ---
**Author:** ![Pleonast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pleonast/32/1183_2.png) [@Pleonast](https://boards.straightdope.com/u/Pleonast)\ **Post date:** [April 5, 2023, 8:21pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/17 "2023-04-05T20:21:18Z")
Slightly related: I’m very particular about the font I use when writing or reading code. My test word is Il1O0S5, and I need to be able to easily read the differences. The Courier font fails, but is far too often the default fixed-width font. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 5, 2023, 11:43pm UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/18 "2023-04-05T23:43:24Z")
> [@What\_Exit](#): > > I can see a clear difference between the O in motor and 0 in 121015. once I zoom in. Those are both printed with really big pixels, and they’re the same pixels. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [April 6, 2023, 1:43am UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/19 "2023-04-06T01:43:08Z")
Agree w @Chronos. The “O” in motor and the maybe-“0” in the serial number have the exact same pattern of the exact same dots. You can count them individually. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [April 6, 2023, 8:05am UTC](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208/20 "2023-04-06T08:05:36Z")
> [@LSLGuy](#): > > Where exactly do you attach a serif to a O or a 0? Way back in the 1960’s, I was taught in computer systems to write capitol O with a little loop at the top of the O, so it was clearly a letter. Rather like the Palmer Penmanship letters we learned in grade school cursive handwriting. [Next page](https://boards.straightdope.com/t/griping-about-part-numbers-and-serial-numbers/982208.md?page=2)