Shares of Turtle Beach Corp. HEAR, +1.94% slumped in Thursday’s extended session after the maker of gaming headsets announced an acquisition and issued a disappointing outlook for the first quarter. Turtle Beach said it plans to buy Roccat, a computer peripherals company, for $14.8 million in cash, net of a working capital adjustment, $1 million in cash or stock, and up to $3.4 million in earnout payments. Once the deal is finalized in the second quarter, Roccat is expected to add to Turtle Beach’s revenue by about $20 million to $24 million. Turtle Beach also reported its fourth-quarter earnings rose to $24.6 million, or $1.33 a share, from $14.2 million, or $1.15 a share, a year earlier. Revenue grew 40% to $111.3 million. Analysts surveyed by FactSet Research had forecast earnings of $1.31 a share on revenue of $110 million. The company projected first-quarter adjusted earnings per share of 5 cents, below Wall Street’s average estimate of 7 cents. Turtle Beach shares sank 13% after hours.

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