Managers of Sleep Quarters at Clark’s Pond in South Portland, relax on one of their Tempur-Pedic beds.Gordon Chibrosk | Portland Press Herald | Getty ImagesTempur Sealy International Incsaid on Tuesday it would buy retailer Mattress Firm in a cash-and-stock deal valued at about $4 billion, as the leading bedding maker looks to grow its business and stem a post-pandemic weakness in sales.Mattress companies have seen a slowdown in sales in the past several quarters, struggling to sustain the explosive growth in demand seen during the early months of the pandemic, when consumers upgraded their home furnishing.The deal would give the combined company a footprint of about 3,000 stores globally, 30 online platforms and 71 manufacturing facilities. Tempur Sealy expects the deal to add to adjusted per-share earnings before synergies in the first year post-close. The deal is expected to close in the second half of 2024.”I don’t think it’s any harder to go through a downturn with Mattress Firm than it would be to go through it without,” Tempur Sealy CEO Scott Thompson said.Mattress Firm, part-owned by Steinhoff International Holdings NV, is among the biggest bedding retailers in the United States, with more than 2,300 brick-and-mortar store locations.Earlier this year, the privately held company withdrew its plans to go public and was exploring options for its business.Lexington, Kentucky-based Tempur Sealy said it would pay about $2.7 billion in cash and $1.3 billion in company stock issued to Mattress Firm shareholders. After deal closure, Mattress Firm would operate as a separate business unit within Tempur Sealy.Tempur Sealy added it has received a request for additional information and documentary material from the Federal Trade Commission. Tempur Sealy executives said in an earnings call negotiations with the FTC were in the “early innings.”The companies believe they can ultimately clear the process either traditionally or through litigation and said they were considering all options to ensure closing, including store divestitures.Shares of Tempur Sealy, which separately reported better-than-expected first-quarter profit, were up about 6%.