The 407780A-NIST is an integrating sound level meter with USB. The meter takes Leq and SEL measurements with A and C frequency weighting options. The meter has a built in datalogger that records up to 32,000 records and PC interface to easily access your logged information. Its 4 digit multifunction LCD has an analog bargraph and digital reading. With the 407780A-NIST you can program integration times, utilize impulse, fast or slow response settings and benefit from alarm features. Complete with windscreen, adjustment screwdriver, USB cable, Windows compatible software, battery, one year warranty and case. Includes certificate traceable to NIST.