Dwyer 160G Air Flow Grid with Precision Sensing measures airflow, velocity, and differential pressure when connected to a manometer. The Dwyer 160G features 16 different sensing points for truly accurate measurements, a maximum reach length of 52”, and a 16.5” L x 16.5” W sensing area. The Dwyer 160G is fantastic for measuring face air velocity on registers, grills, exhaust hoods, diffusers, dampers, filters, coils, and similar restrictions.