Multiple Features: Includes Max reading hold, auto power-off, and auto backlight display for user-friendly operation. Compact & Portable Lightweight and easy to carry, perfect for use in factories, homes, schools, and more. Battery-Efficient: Powered by 3 AAA batteries (not included), with low battery indication for convenience and reliability. Noise Filtering Sponge Ball: Equipped with a sponge ball to filter out unwanted noise and ensure precise measurements. Perfect for industrial noise control, neighborhood monitoring, audio calibration, and health and safety assessments.