I use River Country, have 3 of them between my UDS and 2 Webers. They are always spot on my Maverick, have never had to calibrate one of them although you can. Highly recommend and the price is great.
"Big MO Shirley", UDS, Akorn, 2 22in Kettles, Blacktone Griddle & Pizza Oven
I'm Thomas, friends call me T