RKCB

4NT after 1NT, 2NT, 2♣/NT

4NT is quantitative after Heeman and Romexu, if after transfers we didn't find M fit.

When 4 NT is quantitative, we accept the SI by bidding 5m (showing 4+ card suit) or 5NT. 

After sequences 1NT - 2♣ - 2♦ - 4NT and 1NT - 2♣ - 2♦ - 2♥ - 2♠ - 4NT we confirm M fit and accept SI, by answering RKC:

5♣    =    1 or 3 KC

5♦    =    2 KC without M Q

5M    =    0 KC or we do not accept the SI

5oM    =    2 KC with M Q

4NT is RKCB after Texas transfers.