Features of the system include:

1. A variable one no trump opening (12 to 14 not Vulnerable, 17 to 19 vulnerable).
2. Kivi convention: One no trump - four diamonds asks for precise point count; opener bids four hearts with minimum, four spades with average hand and four no trump with maximum. Applies in similar situations when a jump to four diamonds follows a no trump bid.
3. Artificial jump shift to three clubs on powerful hands, permitting other jump shifts to be made pre-emptively.
4. OKUNEFF convention: After a cue bid used to invite three no trump if partner holds a stopper, the lowest possible bid in an unbid suit shows a partial stopper in the opponent's suit. If this is not possible below three no trump, a bid suit may be utilized.
5. Stayman on the second round after a no trump re-bid.