Answers.Body: <p>As jncraton pointed out some numbers have been reused by different sets, however there are other cases too.</p>
  <p>A good example is <a href="https://www.bricklink.com/v2/search.page?q=10242*#T=S" rel="noreferrer">10242 MINI Cooper</a>. During production of this set TLG has decided to change the box from original squarish size, which is designated as 10242-1 on Bricklink</p>
  <p><a href="https://i.sstatic.net/JKDUV.png" rel="noreferrer"><img src="https://i.sstatic.net/JKDUV.png" alt="enter image description here" /></a></p>
  <p>to rectangular version of the box, so Bricklink used 10242-2 to mark this change.</p>
  <p><a href="https://i.sstatic.net/CJJKs.png" rel="noreferrer"><img src="https://i.sstatic.net/CJJKs.png" alt="enter image description here" /></a></p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-22T18:54:41.963Z
Answers.Text: Same thing occurred for the box of 31313, but I don't think that BL knows that the box of 31313 changed, which is why you only see the original box design. I'll submit an inventory addition request.
Answers.UserDisplayName: mindstormsboi
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-22T19:14:26.903Z
Answers.Text: @mindstormsboi That's interesting. I have only heard of slight design change of outer sleeve. How did the change of dimensions you've mentioned affected the design of the inner sleeve? These must be different too then?
Answers.UserDisplayName: Alex
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-22T19:15:12.123Z
Answers.Text: Oh wait, I meant sleeve, you're right. BL doesn't seem to know about it though.
Answers.UserDisplayName: mindstormsboi
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-22T16:17:27.307Z
Answers.LastActivityDate: 2020-06-22T16:17:27.307Z
Answers.UserDisplayName: Alex
Answers.Body: <p>TLG hasn't always been particularly careful about their set numbering, so the community has taken to adding -1 to the end of the set number to handle cases where there may be duplicate set numbers used by TLG. For example, here's what we refer to as 8858-1:</p>
  <p><a href="https://i.sstatic.net/5Dc72.jpg" rel="noreferrer"><img src="https://i.sstatic.net/5Dc72.jpg" alt="8858-1" /></a></p>
  <p>And 8858-2:</p>
  <p><a href="https://i.sstatic.net/wumdl.jpg" rel="noreferrer"><img src="https://i.sstatic.net/wumdl.jpg" alt="8858-2" /></a></p>
  <p>As others have pointed out, this also helps to track minor adjustments to sets (re-releases, box differences, inventory adjustments, etc). Bricklink maintains a <a href="https://www.bricklink.com/catalogRelCat.asp?relID=18" rel="noreferrer">list</a> of sets that are similar and have the same official set number but which are assigned unique suffixes for various reasons.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-23T03:32:43.250Z
Answers.Text: Mind blown that the later one was assigned -1 and the earlier one was assigned -2.
Answers.UserDisplayName: shoover
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-23T03:39:49.490Z
Answers.Text: That Engines Expert Builder Set looks really nice for such a limited number of pieces. I wish more modern sets would replicate mechanical engineering solutions like that with simple building blocks, instead of applying excessive attention to visual detail with weirdly shaped custom parts that are almost un-reusable in any other configuration.
Answers.UserDisplayName: Will
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-23T09:30:56.313Z
Answers.Text: @Will Well, the weird parts mean people will buy more... it's the sad ugly truth.
Answers.UserDisplayName: Nelson
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-23T17:04:07.057Z
Answers.Text: @Will Mechanical engineering solutions like that with simple building blocks? In this case I highly recommend Yoshihito Isogawa's books and youtube channels. Definitely check them out if you don't know them already...
Answers.UserDisplayName: Uli
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-24T04:28:41.227Z
Answers.Text: Why is 8858-2 used for the *older* set?  Is it just that 8858-1 was added to some database first?  Personally I think it would be more sensible to omit the `-1` *until* there's a numbering collision, or distinguish them by release release (e.g. "8858 (1980)" and "8858 (1994)").
Answers.UserDisplayName: jamesdlin
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-22T12:34:55.047Z
Answers.LastActivityDate: 2020-06-22T19:22:57.527Z
Answers.LastEditDate: 2020-06-22T19:22:57.527Z
Answers.UserDisplayName: jncraton
Answers.Body: <p>In the 1980s, there was a major set adjustment to the Lego space sets , in North America.
  I know, because I have both sets.
  One is noted as -1 and the other -2, which actually has been helpful in sorting sets.
  It is arbitrary, and I don't see it as the first or second time the same part number used.
  But untill Lego group makes an adjustment, or creates an online catloge of all sets, I don't see brick links actions as objectionable.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-23T13:41:15.323Z
Answers.Text: Which sets are these? Also, I didn't say anything about objecting to it.
Answers.UserDisplayName: Robert Columbia
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-23T13:28:39.660Z
Answers.LastActivityDate: 2020-06-23T13:28:39.660Z
Answers.UserDisplayName: user15506
Body: <p>I've been perusing BrickLink for a while, and I noticed that essentially all sets are listed with a &quot;-1&quot; after the LEGO set number. For example, <a href="https://www.lego.com/en-us/product/enchanted-treehouse-41164" rel="noreferrer">Set 41164, Enchanted Treehouse</a> is listed on BrickLink as <a href="https://www.bricklink.com/v2/catalog/catalogitem.page?S=41164-1" rel="noreferrer">41164-<em>1</em></a>.</p>
  <p>What's the purpose of the &quot;-1&quot;, and more specifically, what would a &quot;-2&quot; or even &quot;-3&quot; set number represent?</p>
  <ul>
  <li>Does it represent a version number (e.g. a revised or post-recall version of the set would be numbered 41164-2)?</li>
  <li>Is this a country code?</li>
  <li>Is it just a site-specific affectation?</li>
  <li>Is it currently unused, but reserved for future use?</li>
  </ul>
  
Tags: <bricklink><set-numbering>
Title: Why does BrickLink append a -1 to so many set numbers?
UserDisplayName: Robert Columbia
ThreadText: # Why does BrickLink append a -1 to so many set numbers?
  
  (Asked by: username_0 on 2020-06-22)
  
  I've been perusing BrickLink for a while, and I noticed that essentially all sets are listed with a "-1" after the LEGO set number. For example, [Set 41164, Enchanted Treehouse](https://www.lego.com/en-us/product/enchanted-treehouse-41164) is listed on BrickLink as [41164-*1*](https://www.bricklink.com/v2/catalog/catalogitem.page?S=41164-1).
  
  What's the purpose of the "-1", and more specifically, what would a "-2" or even "-3" set number represent?
  
  * Does it represent a version number (e.g. a revised or post-recall version of the set would be numbered 41164-2)?
  * Is this a country code?
  * Is it just a site-specific affectation?
  * Is it currently unused, but reserved for future use?
  
  **Tags:** bricklink, set-numbering
  
  ---
  
  ## 3 answers
  
  ### Answer by username_3 on 2020-06-22. Score: 26
  
  TLG hasn't always been particularly careful about their set numbering, so the community has taken to adding -1 to the end of the set number to handle cases where there may be duplicate set numbers used by TLG. For example, here's what we refer to as 8858-1:
  
  [![8858-1](https://i.sstatic.net/5Dc72.jpg)](https://i.sstatic.net/5Dc72.jpg)
  
  And 8858-2:
  
  [![8858-2](https://i.sstatic.net/wumdl.jpg)](https://i.sstatic.net/wumdl.jpg)
  
  As others have pointed out, this also helps to track minor adjustments to sets (re-releases, box differences, inventory adjustments, etc). Bricklink maintains a [list](https://www.bricklink.com/catalogRelCat.asp?relID=18) of sets that are similar and have the same official set number but which are assigned unique suffixes for various reasons.
  
  > **Comments:**
  > **username_4**: Mind blown that the later one was assigned -1 and the earlier one was assigned -2.  
  > **username_5**: That Engines Expert Builder Set looks really nice for such a limited number of pieces. I wish more modern sets would replicate mechanical engineering solutions like that with simple building blocks, instead of applying excessive attention to visual detail with weirdly shaped custom parts that are almost un-reusable in any other configuration.  
  > **username_6**: @Will Well, the weird parts mean people will buy more... it's the sad ugly truth.  
  > **username_7**: @Will Mechanical engineering solutions like that with simple building blocks? In this case I highly recommend Yoshihito Isogawa's books and youtube channels. Definitely check them out if you don't know them already...  
  > **username_8**: Why is 8858-2 used for the *older* set?  Is it just that 8858-1 was added to some database first?  Personally I think it would be more sensible to omit the `-1` *until* there's a numbering collision, or distinguish them by release release (e.g. "8858 (1980)" and "8858 (1994)").  
  
  ---
  
  ### Answer by username_1 on 2020-06-22. Score: 14
  
  As jncraton pointed out some numbers have been reused by different sets, however there are other cases too.
  
  A good example is [10242 MINI Cooper](https://www.bricklink.com/v2/search.page?q=10242*#T=S). During production of this set TLG has decided to change the box from original squarish size, which is designated as 10242-1 on Bricklink
  
  [![enter image description here](https://i.sstatic.net/JKDUV.png)](https://i.sstatic.net/JKDUV.png)
  
  to rectangular version of the box, so Bricklink used 10242-2 to mark this change.
  
  [![enter image description here](https://i.sstatic.net/CJJKs.png)](https://i.sstatic.net/CJJKs.png)
  
  > **Comments:**
  > **username_2**: Same thing occurred for the box of 31313, but I don't think that BL knows that the box of 31313 changed, which is why you only see the original box design. I'll submit an inventory addition request.  
  > **username_1**: @mindstormsboi That's interesting. I have only heard of slight design change of outer sleeve. How did the change of dimensions you've mentioned affected the design of the inner sleeve? These must be different too then?  
  > **username_2**: Oh wait, I meant sleeve, you're right. BL doesn't seem to know about it though.  
  
  ---
  
  ### Answer by username_9 on 2020-06-23. Score: -6
  
  In the 1980s, there was a major set adjustment to the Lego space sets , in North America.
  I know, because I have both sets.
  One is noted as -1 and the other -2, which actually has been helpful in sorting sets.
  It is arbitrary, and I don't see it as the first or second time the same part number used.
  But untill Lego group makes an adjustment, or creates an online catloge of all sets, I don't see brick links actions as objectionable.
  
  > **Comments:**
  > **username_0**: Which sets are these? Also, I didn't say anything about objecting to it.  
  
  ---
  
  