This instrument is designed for environmental noise measurement, noise control engineering monitoring, quality control, and health protection monitoring. It is suitable for use in factories, offices, audio-visual venues, transportation areas, homes, and construction sites where noise monitoring and control are required. Features: 1. Large digital LCD display with clear numerical readout for easy viewing. 2. Simple operation—no configuration required; ready to use immediately after power-on. 3. Measurement range: 30–130 dB with adjustable upper and lower limit alarms. 4. Alarm duration adjustment range: 5–120 seconds (factory default: 120 seconds). 5. Audible alarm output: emits a buzzer sound when the measured value reaches the preset alarm level; holds the displayed data for 5 seconds before returning to normal operation. 6. Built-in hanging holes for wall mounting. 7. Suitable for sound level checking and monitoring in personal, household, commercial, educational, and industrial applications. Specifications: 1. Measurement Range: 30–130 dB 2. Frequency Response Range: 31.5 Hz–8.5 kHz 3. Frequency Weighting: A-weighting 4. Response Speed: 8 readings per second 5. Accuracy: ±1.5 dB (when calibrated with a 94 dB, 1000 Hz sound calibrator) 6. Resolution: 1 dB at 100 dB 7. Power Supply: DC 5 V, 1 A 8. Power Input Port: USB Type-C 9. Operating Temperature: 0–40 °C 10. Operating Humidity: 10–80% RH 11. Storage Temperature: –10–60 °C 12. Storage Humidity: 10–70% RH Material: ABS Item Dimensions: 22.5 × 12.5 × 3 cm (8.86 × 4.92 × 1.18 in) Item Weight: 440 g (15.52 oz) Package Dimensions: 24.5 × 16.9 × 3.5 cm (9.64 × 6.65 × 1.38 in) Package Weight: 600 g (21.16 oz) Package Includes: 1 × Noise Meter 1 × USB Type-C Power Cable 1 × User Manual (English)