The MK-III sensor assembly has been designed to offer improved durability and serviceability. This sleek new design is 33 inches high and weighs just over 7 pounds. It is the most accurate, durable and easiest to install weather station available. The long range MK-III-LR features a powerful new 2.4 GHz spread spectrum radio that increases range to 1 mile line of sight. It also features an industry best, real time 2 second wind speed and direction update interval.