Sound level meter for noise test,small shape and convinient. Measurement Range:30--130dB Accuracy:+-2dB Resolution:0.1dB Sample rate : 4 times/s , 1 times/s RS232 interfaceData store functionData holdBack light Low power indication Date and time display Auto/Manual range selectionFast/Slow response selectable MAX value hold function Battary voltage : 6 x 1.5V (AAA) MLS6701 digital noise meter