OATEY 38995 Metal, 1/4 Turn, Copper, Hammer, 2" Rubber Tailpiece - Standard Pack

Either. The 38995 allows a left or right hand drain, so you do not have to hand the box to the room. Pick the side that keeps the standpipe out of the way of the machine and the supply lines.

The drain opening is 2 inches and takes three ways of making up: a rubber coupling, solvent weld, or threaded. That means you can tie into 2 inch PVC with cement, thread into an adapter, or slip a rubber coupling over an existing stub, including cast iron or an odd OD where a glued joint will not work.

Hammer arresters are part of this configuration, not an add-on. The 38995 is the valve-with-hammer build on a copper tailpiece, so the shock absorption for the quick-closing solenoid valves in the washer is already in the box. Nothing extra to tee in above it.

Copper tailpieces, which means you solder to them. Rough in your hot and cold with copper stubs to the box and sweat the joints, or use press or push-to-connect fittings rated for copper tube if you are avoiding an open flame in an occupied unit. There is no threaded supply inlet on this one.

The box ships with its two metal support brackets, the quarter turn valves, the hammer arresters, and the copper tailpieces, so the box itself is complete. What is on you is the copper to reach the tailpieces and solder or press fittings, the 2 inch drain material for whichever make-up you chose (PVC and cement, a threaded adapter, or a rubber coupling), the standpipe and trap, and washer hoses.

The box is 20-gauge steel rather than plastic, so it holds its shape when drywall is screwed tight around it and takes the weight of the valve assembly without flexing. Finish is white, which is what you want if it is going on a painted laundry wall next to other white plates.