Concept Two-bids (CK2s)
Concept Preempts
Always weak (fewer than 10 HCP)
2D = 6.Diamonds or 5.Hearts
2H = 6.Hearts or 5.Spades
2S = 6.Spades or both minors
Responses
(a)Bid next higher suit to play. Opener rebids first suit if 6 card suit and does not have 5 cards in higher suit.
(b) pass to play