A drawing of a <a href="https://en.wikipedia.org/wiki/2N3055" class="extiw" title="en:2N3055">2N3055</a> silicon NPN power transistor in TO-3 transistor package (flanged metal can package). This IC has 3 leads, one of which is the metal case.
<a href="//commons.wikimedia.org/wiki/User:Inductiveload" title="User:Inductiveload">Inductiveload</a>
2010-02-18
<span class="int-own-work" lang="en">Own work</span>, Drawn in SolidEdge and Inskcape