Abstract: A flush-mount connector system is provided for use in attaching supply line valves and drain elbows to in-wall plumbing lines without a conventional in-wall outlet box. The system desirably includes at least one mounting plate, at least one valve holder or drain elbow, and a removable cover panel. The valve holder and drain elbow are each insertable from the rear into engagement with a hole in the mounting plate and are easily rotatable inside the hole to position an attached valve, valves or drain elbow as needed for connection to the in-wall plumbing lines.