Extech 407760 USB Sound Level Meter with Datalogging measures sound from 30 to 130dB with full datalogging capabilities. The Extech 407760 stores and recalls up to 129,920 readings that are capable of being transferred to a PC via USB connection to be analyzed further. This unit also features an 0.5" electret microphone, selectable data sampling rate, and time-stamped recordings.