The chief features of the system are:

1. One club is forcing, and is bid with any balanced hand unsuitable for a one no trump opening (14-16) or a two no trump or a two no trump opening (20-21). One diamond is a negative response and may be made with less than 7 points and may be made with as many as ten.
2. One diamond shows a strong unbalanced hand with 17 or more high card points. A one heart response is negative.
3. One heart and one spade openings show five card suits with 12-16 points in high cards.
4. Two clubs shows a minor two-suiter (4 - 4 or 5 - 4) with 14-16 points.
5. Two diamonds is like two clubs but with major suits.
6. Two hearts and two spades are strong but not forcing (8 playing tricks).
7. Three clubs and three diamonds show 12-16 points and a six or seven card suit missing a top honor.