1-3 is actually a Splinter in the 13-15 dummy point range, despite being called weak.. Opener can sign off at 4 with no interest in slam, or may bid 3N to ask responder to bid the suit with the singleton/void.
1-4/4/3N shows a singleton/void in Clubs, Diamonds, or Spades, respectively, with 16+ dummy points.
Also see Random Splinters which can be used to show normal or strong hands while not identifying the suit unless asked by opener.
-3
is actually a Splinter in the 13-15 dummy point range, despite being called weak.. Opener can sign off at 4
/4
/3N shows a singleton/void in Clubs, Diamonds, or Spades, respectively, with 16+ dummy points.