I bought one of these.... hxxp://www.ebay.com/itm/141055626841?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649 Pretty slick. $40 with 3 senders. Took 8 days to arrive from China. I have one sender in the flowering room, one in the veg tent and one in the curing/cloning closet. Now, I can monitor temp and humidity in all 3 areas right from my desk. I am calibrating it against my Acu-rite to see just how close it is. Acu-rite is a pretty good make and has always been accurate. Setup was easy. It requires 8 - AAA batteries which are not included. 2 for each unit. Plus, it gives me a clock on my desk. I love toys. LOL I'll report on the accuracy in a few days.