The lowest suit step in the game zone shows values for a raise to five but no more, and hands over the role of controller to partner.

WestNorthEastSouth
A621pass
109861pass1pass
A82pass2pass
KJ32?
Bid 4, agreeing spades and showing values for the five level. Partner can sign off in 4 or, with extra values, continue with any other slam tool.

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