If you just need wind speed, this is the handheld wind meter for you! WM-100 includes a wind vane to assure correct alignment to the wind axis. The jackknife case allows more precise wind speed readings because the users hand is distant from the wind impeller, which then measures undisturbed air flow. WM-100 has Swiss-made impeller components, is water resistant and shockproof. For long-range shooting, the unit can be tripod-mounted and uses the optional wind tunnel, Model SM-WT for very precise measurements. All WindMate wind meters are designed with a wind speed accuracy of better than +/- 3%.