The Extech SL510 is a High-Accuracy Sound Level Meter with A and C Weighting, and Fast/Slow Response Modes. Extech's SL510 ultra-compact sound meter meets class 2 standards with ±1dB high accuracy that allows for quick and reliable sound level testing. It features a large backlit display for easy viewing and measures A & C weighting from 35 to 130dB with Fast and Slow response time mode. Size is small enough to conveniently fit in your pocket.