This signal is used by the Referee to indicate an act of unsportsmanlike conduct or other non-contact foul has occured. Curiously enough, this is also used when a player has deliberately contacted an Official.
PenaltyThese fouls are usually considered to have no impact on the outcome of the play and so are usually treated a dead-ball fouls. They attract a 15 yard penalty.
If treated as a dead ball foul, first give the Deal Ball signal (S7), then begin the signal with both hands at about chest high and then extend them to the side in an unhurried manner until they are fully horizontal.
Finally point to the offending team by streching an arm out from the shoulder to the horizontal.