After knee replacement, I used the DonJoy IceMan CLEAR3 Cold Therapy Unit for about 14 days post surgery.
QR Code Link to This Post
It was a Godsend, and worked very well.
I'd recommend using frozen water filled plastic bottles instead of ice cubes. They last longer, less messy, and much cheaper.
It comes with the Universal Wrap-on Pad and three velcro straps to keep the pad in place where needed.
For more information, see: