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According to a result of Kocinac and Scheepers, the Hurewicz coveringproperty is equivalent to a somewhat simpler selection property: For eachsequence of large open covers of the space one can choose finitely manyelements from each cover to obtain a groupable cover of the space. We simplifythe characterization further by omitting the need to consider sequences ofcovers: A set of reals $X$ satisfies the Hurewicz property if, and only if,each large open cover of $X$ contains a groupable subcover. This solves in theaffirmative a problem of Scheepers.  The proof uses a rigorously justified abuse of notation and a "structure"counterpart of a combinatorial characterization, in terms of slaloms, of theminimal cardinality b of an unbounded family of functions in the Baire space.In particular, we obtain a new characterization of $\b$.Comment: Small update

The Hurewicz covering property and slaloms in the Baire space