Feature: 1. CLEAR AND INTUITIVE DISPLAY: Digital frequency meter uses a 0.56in LED font size to display the distribution of data in a concise form, so that readers can quickly understand the data 2. EASY INSTALLATION: The digital display frequency meter has a 68x68mm opening size, possess small size, and can be installed anywhere, very versatile 3. WIDE APPLICABILITY: Frequency meter can be used in various fields, such as industrial automation, mechanical and electrical equipment, distribution box, industry, etc., has strong versatility 4. TECHNICAL PARAMETERS: Digital cymometer with auxiliary power supply AC 80-500V, frequency measuring range 10-99.9Hz, high measurement accuracy of 1%(±2 digits) 5. SCRATCH RESISTANT ABS: AC frequency meter adopt excellent ABS material, impact resistant, scratch resistant, suitable for pure AC 50-61Hz mains power supply Specification: Item Type: Digital Frequency Meter Model: For CH 72 Material: ABS Power Supply: AC50-500V Frequency Range: 10-99.9Hz Measurement Accuracy: 1% (±2 digits) Product Size: Approx. 72 x 72 x 32mm / 2.83 x 2.83 x 1.26in Cutout Size: Approx. 68 x 68mm / 2.68 x 2.68in Display Color: Red LED Font Size: Approx. 14.2mm / 0.56in Package List: 1 x Digital Frequency Meter 2 x Installation Accessories Note: This meter is only suitable for pure AC 50-61Hz mains power, and cannot be used to measure square waveform, inverter output, or modified sine waveform sinusoidal circuits, otherwise the meter will be permanently damaged!