MASTECH MS6708 Digital Sound Level Meter DB: Displays the measured sound level in decibels (dB). Backlight: Turns on the display backlight for easy viewing in low-light conditions. Low Battery: Indicates when the batteries are low and need to be replaced. Mode Select: Allows you to select the desired measurement mode, such as A-weighting, C-weighting, or fast/slow response. Data Hold: Freezes the current reading on the display for easy viewing and recording. This digital sound level meter is widely used to test noise at work, occupational noise, and environmental and community noise. It is also used in vehicle noise testing and other specialized applications.