Product review (5 stars): I connected this to my ice maker water line. ...
I connected this to my ice maker water line.  I have a coil of copper pipe and it would rattle after the ice maker filled up.  That sudden stop would make a bang and a rattle behind the fridge.  I installed this unit as close to the fridge as was reasonable and the noise is nearly all gone.  Plastic pipe would be quieter but copper is more durable and I don't want a burst pipe.  This unit allows me the copper pipe at nearly no noise.