I play a natural 5-card major system, but show number of controls after a 2-club opening, so: 2C - 2UT(4 controls, A=2, K=1) 3D - 4D 4UT (RKC 1430) - 5H 5UT (extras?)- 6SP 7UT I think it is better here to show diamond support immediately after dealer's 3D, rather than to show the spade suit as a possible alternative trump suit, which might leave dealer with the problem of what to bid next. 4UT might seem unnecessary, since dealer already knows how many aces partner has, but I'm not sure how otherwise to ask for extras, and here 4UT followed by 5UT does the job. For me, 5UT direct after partner's 4D would ask parter to bid 6D/7D according to how many diamond top honours he holds. After 5UT, I think it's best that partner now shows the spades, rather than bid 7D. Dealer then should have sufficient information to bid an inspired 7UT, or maybe I'm also influenced by seeing all the cards!.