This all-in-one kit pairs the REED R8050 dual-range sound level meter with the R8090 acoustic calibrator, so you can verify your readings are accurate right in the field. It comes packed in a rugged hard case with custom-cut foam, along with a windscreen and batteries, meeting IEC 61672-1 Class 2 standards for reliable A/C-weighted noise measurements from 30 to 130 dB.