A variation of two way Stayman.

2D demands opener to bid the longer four card major.

Responder then passes to show a weak major two-suiter.

Other bids are forcing to game.

A 2NT re-bid by responder asks opener to bid the four card suits up the line.

Two diamonds response to a 1 N/T opening demands the opener to bid his best major regardless of the length (even with only 3).

The bid promises at least 5 of a major.

After the opener bids his best major, partner may:

Pass - If he has a poor hand and partner named his suit.

Raise the suit picked by his partner

Return to N/T if his partner names the wrong suit.