Make sound measurements with greater precision and convenience. Simple operation is ideal for classroom use. Easy to read digital display with analog bargraph. Bargraph updates every 40 mS to display trends. Measures 40 to 130dB with ±2 dB accuracy. User can select A or C weighting and fast or slow response time. Max. Hold function captures the peak reading. Includes 4 AAA batteries. Size: 23 cm x 5.7 cm x 4.4 cm.