informal details of immediate practical importance
get down to brass tacks
to tackle the essential or practical issues involved in a task or undertaking
[The brass tacks may originally have been those fixed to the counters of drapers’ shops for measuring lengths of cloth, but other applications may also have been involved in the evolution of the phrase. The suggestion that it is rhyming slang for ‘facts’ or ‘hard facts’ is no more than a rationalization]