Preempt Roman Key Card Blackwood
After a weak two bid opening or a three-level preemptive opening bid from partner, a 4♣ bid by responder asks for keycards with different steps responses.
It should be apparent that the normal responses are of much less significance after a preemptive opening bid has been made. The steps responses are as follows:
1st step = 0 Key Cards
2nd step = 1 Key Card without the Trump Queen
3rd step = 1 Key Card with the Trump Queen
4th step = 2 Key Cards without the Trump Queen
5th step = 2 Key Cards with the Trump Queen
Voids are not shown with this treatment.
There is one exception: after a 3♣ opening bid, the Preempt Roman Key Card Blackwood bid is 4♦.
SOURCE: "Conventions", The Official ACBL Encyclopedia of Bridge, 7th ed. Horn Lake: American Contract Bridge League, Inc., 2011, page 308. Print