This activator is not bounded to anything like button, blocks or regions.
But it could be executed by command /react run [playername] [delay]
and... by another activator (using action "run")
To create this activator use command:
/react add exec <ActivatorId> [player:<PlayerSet>] [delay:<Time>]
To execute this activator you must type commands:
/exec <ActivatorId> — to run this activator without delay/exec <ActivatorId> player:<PlayersSet> — to run this activator for player without delay/exec <ActivatorId> player:<PlayersSet> delay:<Time> — to run this activator for player after time defined at delay/exec Activator player:fromgate delay:01:05 — will execute activator with id Activator after one minute and five seconds for player fromgate./exec Activator player:{region world.spawns} delay:15s — will execute activator with id Activator after 15 seconds for every player in region named spawn in world "world"