Binary digits (5)
'binary digits' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for ones that I've seen before include "Units" , "(Of ship) returning to port of origin" , "1 & 1 & 1" , "Singles" , "Individuals" .)
(Other definitions for zeros that I've seen before include "ducks" , "loves" , "Noughts" , "zips" , "nothings" .)