Answers.Body: <p>When your function (such as an extending crane boom) gets to one limit or the other, this clutch gear ratchets instead of binding up the motor and all the gears in between.</p>
  
  <p>ETA: Forgot the second question. It has appeared in <a href="http://www.bricklink.com/catalogItemIn.asp?P=60c01&amp;in=S">many sets</a>, most recently the <a href="http://www.bricklink.com/catalogItem.asp?S=10244-1">Fairground Mixer</a>.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2014-07-29T09:43:48.140Z
Answers.LastActivityDate: 2014-07-29T20:44:26.310Z
Answers.LastEditDate: 2014-07-29T20:44:26.310Z
Answers.UserDisplayName: gev
Body: <p>I have just bought this set and wonder the purpose of the white gear in the middle:
  <img src="https://i.sstatic.net/mLC1P.jpg" alt="Gear"></p>
  
  <p>How can you use it in your Lego Technic projects? Is it available in other sets?</p>
  
Tags: <technic><gears><piece-usage>
Title: What's the purpose of the clutch gear in Power Functions set?
UserDisplayName: Sergei Basharov
ThreadText: # What's the purpose of the clutch gear in Power Functions set?
  
  (Asked by: username_0 on 2014-07-29)
  
  I have just bought this set and wonder the purpose of the white gear in the middle:
  ![Gear](https://i.sstatic.net/mLC1P.jpg)
  
  How can you use it in your Lego Technic projects? Is it available in other sets?
  
  **Tags:** technic, gears, piece-usage
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2014-07-29. Score: 13 | Accepted answer
  
  When your function (such as an extending crane boom) gets to one limit or the other, this clutch gear ratchets instead of binding up the motor and all the gears in between.
  
  ETA: Forgot the second question. It has appeared in [many sets](http://www.bricklink.com/catalogItemIn.asp?P=60c01&in=S), most recently the [Fairground Mixer](http://www.bricklink.com/catalogItem.asp?S=10244-1).
  
  
  ---
  
  