take it or leave it
US /teɪk ɪt ɔːr liːv ɪt/
UK /teɪk ɪt ɔːr liːv ɪt/

1.
used to say that someone must make a decision quickly about something, and that no other offers or changes will be made
:
•
This is my final offer, take it or leave it.
•
I told him it was take it or leave it, and he took it.