The NRG Class 1 Anemometer is a ball-bearing version of our industry-leading NRG 40C Anemometer. That is, it relies upon the same compact external form factor for easy transport and installation. Inside, the patented dual shaft design of the NRG Class 1 protects the bearings from debris and the common impact loads experienced in harsh climates, while the bearings themselves deliver the low friction necessary to achieve certified class 1 performance.