I was looking for a housing to put in the wall that I could use not as an ice-maker supply line but rather as a drain for my Water Softener's brine tank. I was able to drill out the bottom hole to accept a 3/4" MPT (Male Pipe Thread) copper adapter with a sweat connection on the other end secured with a pair of 3/4" EMT lock nuts. This let me insert a 5/8-inch outer diameter PE tube (see: http://www.amazon.com/dp/B000UH4JD2/ ) that connected from the brine tank directly into the hole in the housing which I plumbed to an existing copper line that led to the side of the house.It was easy enough to mount the housing in between a pair of 2x4 studs to make sure that it did not go anywhere and the 5/8" drywall fit over the box easy enough and allowed me to snap the cover in place. Looks very nice.The attached photo shows the enlarged hole to accommodate a 3/4" MPT to copper sweat adapter. I used EMT lock nuts on both sides to secure the box to the pipe and also enlarged the three holes on the housing to accommodate the SPAX #8 2" T-star screws that I used to secure it to a 2x4. For added stability I drove the 2 nails into a stud on the left. The picture also shows a sample of the 5/8" OD PE tubing I bought here on Amazon.