KT805Б: NPN silicon power transistor, 135 V; 5 A; 30 W.
Produced  in the former Soviet Union, 1978
<a href="//commons.wikimedia.org/wiki/User:Mister_rf" title="User:Mister rf">Mister rf</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>