All Natkon dendrometers are now capable of carrying two sensor heads even when ordered with one sensor only. The new frame design gives you the option to upgrade any type of dendrometer (O-shaped and T-shaped frames) to a dual-dendrometer.
Dual-dendrometers get increasingly asked since they are able to measure over-bark and on-xylem responses of trees in parallel. The combination of the two signals additionally allow for detecting sugar loading and unloading processes in the bark.