Answers.Body: <p>That is the <a href="https://www.bricklink.com/v2/catalog/catalogitem.page?P=bb0085&amp;name=Vehicle,%20Trailer%20Base%204%20x%2013&amp;category=%5BVehicle,%20Base%5D#T=C&amp;C=5" rel="noreferrer">Vehicle, Trailer Base 4 x 13</a>. It came in one set, the <a href="https://www.bricklink.com/v2/catalog/catalogitem.page?S=378-1#T=S&amp;O=%7B%22iconly%22:0%7D" rel="noreferrer">#378 Tractor</a> from 1972.</p>
  <p>Found by searching first 4x9 (didn't find it) and then 4x13 (the total length).</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-11-26T06:40:07.423Z
Answers.LastActivityDate: 2020-11-26T06:40:07.423Z
Answers.UserDisplayName: shoover
Body: <p>I cannot find a part number on it. It has the official logos on the studs. What is this? What theme does it originate from?<a href="https://i.sstatic.net/ZeMR2.jpg" rel="noreferrer"><img src="https://i.sstatic.net/ZeMR2.jpg" alt="combination of a 4x4 plate, a 5x2 plate and an arc with a ball joint" /></a></p>
  <p>It looks like a combination of a 4x4 plate, a 5x2 plate and an arc with a ball joint.</p>
  
Tags: <part-identification>
Title: What LEGO piece is this arc with ball joint?
UserDisplayName: hanswesterbeek
ThreadText: # What LEGO piece is this arc with ball joint?
  
  (Asked by: username_0 on 2020-11-26)
  
  I cannot find a part number on it. It has the official logos on the studs. What is this? What theme does it originate from?[![combination of a 4x4 plate, a 5x2 plate and an arc with a ball joint](https://i.sstatic.net/ZeMR2.jpg)](https://i.sstatic.net/ZeMR2.jpg)
  
  It looks like a combination of a 4x4 plate, a 5x2 plate and an arc with a ball joint.
  
  **Tags:** part-identification
  
  
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  ## 1 answers
  
  ### Answer by username_1 on 2020-11-26. Score: 27 | Accepted answer
  
  That is the [Vehicle, Trailer Base 4 x 13](https://www.bricklink.com/v2/catalog/catalogitem.page?P=bb0085&name=Vehicle,%20Trailer%20Base%204%20x%2013&category=%5BVehicle,%20Base%5D#T=C&C=5). It came in one set, the [#378 Tractor](https://www.bricklink.com/v2/catalog/catalogitem.page?S=378-1#T=S&O=%7B%22iconly%22:0%7D) from 1972.
  
  Found by searching first 4x9 (didn't find it) and then 4x13 (the total length).
  
  
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