Extech 451126 CFM/CMM Vane Anemometer Datalogger Datalogging vane anemometer measures air, velocity, or air volume and temperature Dual display provides "air velocity + temperature" or "air flow + area" readings Measures air flow in CFM (Feet3/min) and CMM (meters3/min) Internal 1000 point datalogger Built-in RS-232 PC interface