Product review (1 stars): A complete waste of money.
What I really wanted was a wireless humidity sensor that would communicate directly over wifi.  This is not that product.

This device requires that you plug a secondary indoor "gateway" device directly into a port of your home router.  This gateway communicates via radio frequency with the outdoor wireless sensor unit.  The range of this device is quite limited.  I had to try several locations for the outdoor unit before I could even get a signal.

The inside gateway when powered on, made an incessant whine.  To my great relief, one day (after two or three weeks) it stopped working entirely.

I was a fool to have purchased this product despite its poor reviews.