Photo Tachometer DT2234C (Laser) is applicable to the product departments of motor, fan, paper-product, plastics, chemical fiber, washing machine, automobile airplane, steamer etc. Built-in laser for non-contact measurements up to 3.5 feet away. Narrow beam laser for accurate non-contact RPM measurements Microprocessor based high resolution and accuracy. Feature: Built-in laser for non-contact measurements up to 3.5 feet away. Narrow beam laser for accurate non-contact RPM measurements Microprocessor based, high resolution and accuracy 5-digit large LCD display, with min. & max value memory Wide measuring range and high resolution Measures exact RPM with no guessing or errors Memorized the last value, max. Value and min. value Low battery power indication Specification: 5 digits 18mm (0.6) LCD Accuracy: ± (0.05%+1 digit) Sampling Time: 0.5sec (over 120RPM) Range Select: Auto-Ranging Memory: Max. Value, Min. value, Last value Measuring Range: 2.5~99,999RPM Resolution: 0.1RPM (2.5~999.9RPM) & 1RPM (over 1,000RPM) Detecting Distance: 50~500mm Battery: 4x1.5V AA battery Time Base: 6MHz Quartz crystal Time Base Accuracy: 10x10-6(0~50°C) Power Consumption: Approx 40mA Dimension: 18.4Lx7.6Wx3.0H (cm)