CHECK-BACK STAYMAN

Check-back is a convention used after 1x-1y-1NT (showing 12-14 or 15-17). 

2C from the responder show at least an invitational hand. This bid is a kind of Staymand and ask for major.

Responses are:

• 2D: not any extra majorlength.
• 2 in unbid major: 4 card.
• 2 in responders majorsuit: 3 card support.
• All bids from 2N and higher show a maksimum hand.