Double offset supply lines are most popular for tub- wall mount faucets which commonly have 3-3/8″ centers. The supply lines are angled and slopes slightly outward from the faucet. At the floor, the plumbing for double offset supply lines should be roughed in at 8-3/8″ on center. on a 3-3/8″ faucet spread. We offer our Double Offset Supply Lines in 3 metal finishes: Chrome, Satin Nickel, and Old World Bronze.