Unusual 2NT is an opening bid or a jump overcall made by the first defender. 

There are two situations:

• an opening bid:

W N E S

2N*

*1 Unusual 2NT

• • opponents showed 1 suit - two lowers suits:

W N E S

1♦ 2N*

*1 Unusual 2NT, 9+HCP

• • opponents showed 2 suits - shows a weak two-suited hand in the remaining suits:

W N E S

1♦ P 1♥ 2N*

*1 Unusual 2NT, 9+HCP

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