★Maximum and minimum value lock, data storage function, easy to read and data record ★Used to measure the sound level of audio equipment in work and life: such as factories, workshops, schools, residences, office areas, traffic roads, audio, office buildings, restaurants, schools, classrooms, libraries, etc. ★Multiple composite processes, non-slip, drop-proof, dust-proof, waterproof ★Miniature condenser microphone sensor, accidental drop can also protect the sound head from normal use ★If you encounter problems during the purchase process, you can contact by email, and we will reply to you within 1-8 hours, Manufacturer: LLAWQSM