Oatey 3-1/2 in. Center Drain Washing Machine Outlet Box 38120 - The Home Depot
Laundry box + laundry sink : r/Plumbing
Oatey Washing Machine Outlet Box - Ace Hardware
SUNGATOR Laundry Washer Valve Box, Washing Machine Outlet Box, 1/2 Inch Mip (Sweat) Inlet x 3/4 Inch MHT Outlet, Washer Water Faucet Recessed Box with Center Drain - Amazon.com