Actually, it is much smaller diameter than thermapen. Ordered one when they came out and really like the ProSeries probe. A little delicate. You have to be more careful with this probe than say a Maverick.
Smooth Smoke BBQ Team, KCBS CBJ, 2-WSM, Cajun Bandit Conversion, wsm 2880, Smokey Joe Mini wsm, Old Country offset, several kettles.