Firecracker part (4)
I believe the answer is:
fuse
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">firecracker part</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for fuse that I've seen before include "Electrical fitting" , "Melt; ignition device" , "Join, coalesce" , "Common electrical safety device in homes etc" , "Join or blend to form an entity" .)