Casper has named Michael Monahan as its new chief financial officer. He replaces Stuart Brown, who was in the job on an interim basis. Mr. Monahan joins the bed-in-box company as it faces stiff competition from a growing list of rivals. Casper, which reported a five percent gain in sales during its quarter ending on June 30, is seen by many analysts as underperforming. Mr. Monahan said that he sees a “significant runway for growth” at Casper as he joins the company.