Pulley diagram with 4 pulleys.
<a href="//commons.wikimedia.org/wiki/User:Prolineserver" title="User:Prolineserver">Prolineserver</a>, <a href="//commons.wikimedia.org/wiki/User:Tomia" title="User:Tomia">Tomia</a> <small>(minor edits by <a href="//commons.wikimedia.org/wiki/User:Ss181292" title="User:Ss181292">Stanisław Skowron</a>, scale adjusted by <a href="//commons.wikimedia.org/wiki/User:Atropos235" title="User:Atropos235">Atropos235</a>)</small>
CC BY 2.5
<span class="int-own-work" lang="en">Own work</span>