Brass tacks (4,3,5)
I believe the answer is:
nuts and bolts
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">brass tacks</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for nuts and bolts that I've seen before include "available from hardware store" , "Fundamentals" , "Essential basics" , "DDessentials of the ironmonger's trade?" , "Basics - fasteners?" .)