that is what i have. my sink was plumbied with a shut off to the DW, and one on the feed to the fridge, but NONE for the faucet. so i installed new shut offs for the faucet.

you could use 2 shutoffs to kill all 4 things, but using 4 makes it so much nicer if you have a problem later and only want to shut off the water filter or DW to work on them.